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  <front>
    <journal-meta>
      <journal-id journal-id-type="publisher-id">127</journal-id>
      <journal-id journal-id-type="index">urn:lsid:arphahub.com:pub:15f175fc-9690-5d13-a2ea-114d8a2e74bd</journal-id>
      <journal-title-group>
        <journal-title xml:lang="en">Frontiers of Biogeography</journal-title>
        <abbrev-journal-title xml:lang="en">biogeography</abbrev-journal-title>
      </journal-title-group>
      <issn pub-type="epub">1948-6596</issn>
      <publisher>
        <publisher-name>Pensoft Publishers</publisher-name>
      </publisher>
    </journal-meta>
    <article-meta>
      <article-id pub-id-type="doi">10.21425/fob.19.195124</article-id>
      <article-id pub-id-type="publisher-id">195124</article-id>
      <article-categories>
        <subj-group subj-group-type="heading">
          <subject>Research Article</subject>
        </subj-group>
        <subj-group subj-group-type="biological_taxon">
          <subject>Colubridae</subject>
          <subject>Reptilia</subject>
          <subject>Serpentes</subject>
          <subject>Squamata</subject>
          <subject>Vertebrata</subject>
        </subj-group>
        <subj-group subj-group-type="scientific_subject">
          <subject>Biogeography</subject>
          <subject>Conservation</subject>
          <subject>Diversity</subject>
          <subject>Evolution</subject>
        </subj-group>
        <subj-group subj-group-type="geographical_area">
          <subject>Africa</subject>
        </subj-group>
      </article-categories>
      <title-group>
        <article-title>Diversity, origin, and biogeography of a widely distributed genus of African tree snakes (<tp:taxon-name><tp:taxon-name-part taxon-name-part-type="family" reg="Colubridae">Colubridae</tp:taxon-name-part></tp:taxon-name>, <italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadoboa">Dipsadoboa</tp:taxon-name-part></tp:taxon-name></italic>)</article-title>
      </title-group>
      <contrib-group content-type="authors">
        <contrib contrib-type="author" corresp="yes">
          <name name-style="western">
            <surname>Lobón-Rovira</surname>
            <given-names>Javier</given-names>
          </name>
          <email xlink:type="simple">j.lobon.rovira@hotmail.com</email>
          <uri content-type="orcid">https://orcid.org/0000-0003-4380-9427</uri>
          <xref ref-type="aff" rid="A1">1</xref>
        </contrib>
        <contrib contrib-type="author" corresp="no">
          <name name-style="western">
            <surname>Basham</surname>
            <given-names>Edmund W.</given-names>
          </name>
          <uri content-type="orcid">https://orcid.org/0000-0002-0167-7908</uri>
          <xref ref-type="aff" rid="A2">2</xref>
        </contrib>
        <contrib contrib-type="author" corresp="no">
          <name name-style="western">
            <surname>Gvozdik</surname>
            <given-names>Vaclav</given-names>
          </name>
          <uri content-type="orcid">https://orcid.org/0000-0002-4398-4076</uri>
          <xref ref-type="aff" rid="A3">3</xref>
          <xref ref-type="aff" rid="A4">4</xref>
        </contrib>
        <contrib contrib-type="author" corresp="no">
          <name name-style="western">
            <surname>Greenbaum</surname>
            <given-names>Eli</given-names>
          </name>
          <uri content-type="orcid">https://orcid.org/0000-0003-1674-1316</uri>
          <xref ref-type="aff" rid="A5">5</xref>
        </contrib>
        <contrib contrib-type="author" corresp="no">
          <name name-style="western">
            <surname>Badjedjea</surname>
            <given-names>Gabriel</given-names>
          </name>
          <uri content-type="orcid">https://orcid.org/0000-0003-4284-4327</uri>
          <xref ref-type="aff" rid="A6">6</xref>
        </contrib>
        <contrib contrib-type="author" corresp="no">
          <name name-style="western">
            <surname>Bamba-Kaya</surname>
            <given-names>Abraham</given-names>
          </name>
          <uri content-type="orcid">https://orcid.org/0009-0007-2712-7334</uri>
          <xref ref-type="aff" rid="A7">7</xref>
        </contrib>
        <contrib contrib-type="author" corresp="no">
          <name name-style="western">
            <surname>Champagne</surname>
            <given-names>Patrick S.</given-names>
          </name>
          <xref ref-type="aff" rid="A8">8</xref>
        </contrib>
        <contrib contrib-type="author" corresp="no">
          <name name-style="western">
            <surname>Dobbins</surname>
            <given-names>Brittany A.</given-names>
          </name>
          <uri content-type="orcid">https://orcid.org/0009-0006-8258-8646</uri>
          <xref ref-type="aff" rid="A2">2</xref>
        </contrib>
        <contrib contrib-type="author" corresp="no">
          <name name-style="western">
            <surname>Kusamba</surname>
            <given-names>Chifundera</given-names>
          </name>
          <xref ref-type="aff" rid="A9">9</xref>
          <xref ref-type="aff" rid="A10">10</xref>
        </contrib>
        <contrib contrib-type="author" corresp="no">
          <name name-style="western">
            <surname>Loader</surname>
            <given-names>Simon P.</given-names>
          </name>
          <uri content-type="orcid">https://orcid.org/0000-0003-4162-0575</uri>
          <xref ref-type="aff" rid="A11">11</xref>
        </contrib>
        <contrib contrib-type="author" corresp="no">
          <name name-style="western">
            <surname>Lyakurwa</surname>
            <given-names>John V.</given-names>
          </name>
          <uri content-type="orcid">https://orcid.org/0000-0002-8252-0880</uri>
          <xref ref-type="aff" rid="A12">12</xref>
        </contrib>
        <contrib contrib-type="author" corresp="no">
          <name name-style="western">
            <surname>Kouete</surname>
            <given-names>Marcel T.</given-names>
          </name>
          <xref ref-type="aff" rid="A13">13</xref>
        </contrib>
        <contrib contrib-type="author" corresp="no">
          <name name-style="western">
            <surname>Masudi</surname>
            <given-names>Franck M.</given-names>
          </name>
          <xref ref-type="aff" rid="A14">14</xref>
        </contrib>
        <contrib contrib-type="author" corresp="no">
          <name name-style="western">
            <surname>Menegon</surname>
            <given-names>Michele</given-names>
          </name>
          <xref ref-type="aff" rid="A15">15</xref>
          <xref ref-type="aff" rid="A16">16</xref>
        </contrib>
        <contrib contrib-type="author" corresp="no">
          <name name-style="western">
            <surname>Nečas</surname>
            <given-names>Tadeáš</given-names>
          </name>
          <uri content-type="orcid">https://orcid.org/0000-0002-5060-8394</uri>
          <xref ref-type="aff" rid="A3">3</xref>
        </contrib>
        <contrib contrib-type="author" corresp="no">
          <name name-style="western">
            <surname>Penner</surname>
            <given-names>Johannes</given-names>
          </name>
          <uri content-type="orcid">https://orcid.org/0000-0001-8166-5992</uri>
          <xref ref-type="aff" rid="A17">17</xref>
          <xref ref-type="aff" rid="A18">18</xref>
        </contrib>
        <contrib contrib-type="author" corresp="no">
          <name name-style="western">
            <surname>Rödel</surname>
            <given-names>Mark-Oliver</given-names>
          </name>
          <uri content-type="orcid">https://orcid.org/0000-0002-1666-195X</uri>
          <xref ref-type="aff" rid="A18">18</xref>
        </contrib>
        <contrib contrib-type="author" corresp="no">
          <name name-style="western">
            <surname>Tobi</surname>
            <given-names>Elie</given-names>
          </name>
          <xref ref-type="aff" rid="A19">19</xref>
        </contrib>
        <contrib contrib-type="author" corresp="no">
          <name name-style="western">
            <surname>Tolley</surname>
            <given-names>Krystal A.</given-names>
          </name>
          <uri content-type="orcid">https://orcid.org/0000-0002-7778-1963</uri>
          <xref ref-type="aff" rid="A20">20</xref>
        </contrib>
        <contrib contrib-type="author" corresp="no">
          <name name-style="western">
            <surname>Vaz Pinto</surname>
            <given-names>Pedro</given-names>
          </name>
          <xref ref-type="aff" rid="A21">21</xref>
          <xref ref-type="aff" rid="A22">22</xref>
          <xref ref-type="aff" rid="A23">23</xref>
        </contrib>
        <contrib contrib-type="author" corresp="no">
          <name name-style="western">
            <surname>Zassi-Boulou</surname>
            <given-names>Ange-Ghislain</given-names>
          </name>
          <xref ref-type="aff" rid="A24">24</xref>
        </contrib>
        <contrib contrib-type="author" corresp="no">
          <name name-style="western">
            <surname>Zoungrana</surname>
            <given-names>Magali</given-names>
          </name>
          <xref ref-type="aff" rid="A13">13</xref>
        </contrib>
        <contrib contrib-type="author" corresp="no">
          <name name-style="western">
            <surname>Jongsma</surname>
            <given-names>Gregory F. M.</given-names>
          </name>
          <uri content-type="orcid">https://orcid.org/0000-0001-8790-2610</uri>
          <xref ref-type="aff" rid="A25">25</xref>
        </contrib>
      </contrib-group>
      <aff id="A1">
        <label>1</label>
        <addr-line content-type="verbatim">Museo Nacional de Ciencias Naturales (MNCN-CSIC), José Gutiérrez Abascal 2, 28006, Madrid, Spain</addr-line>
        <institution>Museo Nacional de Ciencias Naturales (MNCN-CSIC)</institution>
        <addr-line content-type="city">Madrid</addr-line>
        <country>Spain</country>
        <uri content-type="ror">https://ror.org/02v6zg374</uri>
      </aff>
      <aff id="A2">
        <label>2</label>
        <addr-line content-type="verbatim">Department of Integrative Biology, The University of Texas at Austin, Austin, USA</addr-line>
        <institution>Department of Integrative Biology, The University of Texas at Austin</institution>
        <addr-line content-type="city">Austin</addr-line>
        <country>United States of America</country>
        <uri content-type="ror">https://ror.org/00hj54h04</uri>
      </aff>
      <aff id="A3">
        <label>3</label>
        <addr-line content-type="verbatim">Institute of Vertebrate Biology of the Czech Academy of Sciences, Brno, Czech Republic</addr-line>
        <institution>Institute of Vertebrate Biology of the Czech Academy of Sciences</institution>
        <addr-line content-type="city">Brno</addr-line>
        <country>Czech Republic</country>
        <uri content-type="ror">https://ror.org/05bcgdd94</uri>
      </aff>
      <aff id="A4">
        <label>4</label>
        <addr-line content-type="verbatim">Department of Zoology, National Museum of the Czech Republic, Prague, Czech Republic</addr-line>
        <institution>Department of Zoology, National Museum of the Czech Republic</institution>
        <addr-line content-type="city">Prague</addr-line>
        <country>Czech Republic</country>
      </aff>
      <aff id="A5">
        <label>5</label>
        <addr-line content-type="verbatim">Department of Biological Sciences, University of Texas at El Paso, El Paso, TX 79968, USA</addr-line>
        <institution>Department of Biological Sciences, University of Texas at El Paso</institution>
        <addr-line content-type="city">El Paso</addr-line>
        <country>United States of America</country>
        <uri content-type="ror">https://ror.org/04d5vba33</uri>
      </aff>
      <aff id="A6">
        <label>6</label>
        <addr-line content-type="verbatim">Department of Ecology and Aquatic Biodiversity, Biodiversity Monitoring Centre, University of Kisangani, Kisangani, Democratic Republic of the Congo</addr-line>
        <institution>Department of Ecology and Aquatic Biodiversity, Biodiversity Monitoring Centre, University of Kisangani</institution>
        <addr-line content-type="city">Kisangani</addr-line>
        <country>Democratic Republic of the Congo</country>
        <uri content-type="ror">https://ror.org/028svp844</uri>
      </aff>
      <aff id="A7">
        <label>7</label>
        <addr-line content-type="verbatim">Institut de Recherches Agronomiques et Forestières, Centre National de la Recherche Scientifique et Technologique, BP 842, Libreville, Gabon</addr-line>
        <institution>Institut de Recherches Agronomiques et Forestières, Centre National de la Recherche Scientifique et Technologique</institution>
        <addr-line content-type="city">Libreville</addr-line>
        <country>Gabon</country>
      </aff>
      <aff id="A8">
        <label>8</label>
        <addr-line content-type="verbatim">School of the Environment, The University of Queensland, St Lucia, Queensland, Australia</addr-line>
        <institution>School of the Environment, The University of Queensland</institution>
        <addr-line content-type="city">Queensland</addr-line>
        <country>Australia</country>
      </aff>
      <aff id="A9">
        <label>9</label>
        <addr-line content-type="verbatim">Laboratoire d’Herpétologie, Département de Biologie, Centre de Recherche en Sciences Naturelles, Lwiro, Democratic Republic of the Congo</addr-line>
        <institution>Laboratoire d’Herpétologie, Département de Biologie, Centre de Recherche en Sciences Naturelles</institution>
        <addr-line content-type="city">Lwiro</addr-line>
        <country>Democratic Republic of the Congo</country>
      </aff>
      <aff id="A10">
        <label>10</label>
        <addr-line content-type="verbatim">Laboratory of Ecology and Wildlife Resources Management, Department of Biology, Faculty of Sciences, National Pedagogical University, Kinshasa, Democratic Republic of the Congo</addr-line>
        <institution>Laboratory of Ecology and Wildlife Resources Management, Department of Biology, Faculty of Sciences, National Pedagogical University</institution>
        <addr-line content-type="city">Kinshasa</addr-line>
        <country>Democratic Republic of the Congo</country>
        <uri content-type="ror">https://ror.org/05rrz2q74</uri>
      </aff>
      <aff id="A11">
        <label>11</label>
        <addr-line content-type="verbatim">The Natural History Museum, Cromwell Road, SW7 5BD London, UK</addr-line>
        <institution>The Natural History Museum</institution>
        <addr-line content-type="city">London</addr-line>
        <country>United Kingdom</country>
      </aff>
      <aff id="A12">
        <label>12</label>
        <addr-line content-type="verbatim">Department of Zoology and Wildlife Conservation, University of Dar es Salaam, P.O. Box 35064, Dar es Salaam, Tanzania</addr-line>
        <institution>Department of Zoology and Wildlife Conservation, University of Dar es Salaam</institution>
        <addr-line content-type="city">Dar es Salaam</addr-line>
        <country>Tanzania</country>
        <uri content-type="ror">https://ror.org/0479aed98</uri>
      </aff>
      <aff id="A13">
        <label>13</label>
        <addr-line content-type="verbatim">Division of Herpetology, Florida Museum of Natural History, University of Florida, 32611 Gainesville FL USA</addr-line>
        <institution>Division of Herpetology, Florida Museum of Natural History, University of Florida</institution>
        <addr-line content-type="city">Gainesville</addr-line>
        <country>United States of America</country>
        <uri content-type="ror">https://ror.org/02y3ad647</uri>
      </aff>
      <aff id="A14">
        <label>14</label>
        <addr-line content-type="verbatim">Department of Ecology and Biodiversity of Terrestrial Resources, Centre de Surveillance de la Biodiversité of the University of Kisangani, Kisangani, Democratic Republic of the Congo</addr-line>
        <institution>Department of Ecology and Biodiversity of Terrestrial Resources, Centre de Surveillance de la Biodiversité of the University of Kisangani</institution>
        <addr-line content-type="city">Kisangani</addr-line>
        <country>Democratic Republic of the Congo</country>
      </aff>
      <aff id="A15">
        <label>15</label>
        <addr-line content-type="verbatim">PAMS Foundation, P.O. Box 16556, Arusha, Tanzania</addr-line>
        <institution>PAMS Foundation</institution>
        <addr-line content-type="city">Arusha</addr-line>
        <country>Tanzania</country>
      </aff>
      <aff id="A16">
        <label>16</label>
        <addr-line content-type="verbatim">MUSE, Museo delle Scienze, Viale del Lavoro e delle Scienza, 3, 38122 Trento, Italy</addr-line>
        <institution>MUSE, Museo delle Scienze</institution>
        <addr-line content-type="city">Trento</addr-line>
        <country>Italy</country>
        <uri content-type="ror">https://ror.org/00qxmfv78</uri>
      </aff>
      <aff id="A17">
        <label>17</label>
        <addr-line content-type="verbatim">Frogs &amp; Friends, Reichenberger Str. 88, 10999 Berlin, Germany</addr-line>
        <institution>Frogs &amp; Friends</institution>
        <addr-line content-type="city">Berlin</addr-line>
        <country>Germany</country>
      </aff>
      <aff id="A18">
        <label>18</label>
        <addr-line content-type="verbatim">Museum für Naturkunde Berlin – Leibniz Institute for Evolution and Biodiversity Science, Invalidenstraße 43, 10115 Berlin, Germany</addr-line>
        <institution>Museum für Naturkunde Berlin – Leibniz Institute for Evolution and Biodiversity Science</institution>
        <addr-line content-type="city">Berlin</addr-line>
        <country>Germany</country>
        <uri content-type="ror">https://ror.org/052d1a351</uri>
      </aff>
      <aff id="A19">
        <label>19</label>
        <addr-line content-type="verbatim">Gabon Biodiversity Program, Smithsonian Conservation Biology Institute, Gamba, Gabon</addr-line>
        <institution>Gabon Biodiversity Program, Smithsonian Conservation Biology Institute</institution>
        <addr-line content-type="city">Gamba</addr-line>
        <country>Gabon</country>
      </aff>
      <aff id="A20">
        <label>20</label>
        <addr-line content-type="verbatim">Department of Zoology &amp; Centre for Ecological Genomics and Wildlife Conservation, University of Johannesburg, P.O. Box 524, Auckland Park 2006, Johannesburg, South Africa</addr-line>
        <institution>Department of Zoology &amp; Centre for Ecological Genomics and Wildlife Conservation, University of Johannesburg</institution>
        <addr-line content-type="city">Johannesburg</addr-line>
        <country>South Africa</country>
        <uri content-type="ror">https://ror.org/04z6c2n17</uri>
      </aff>
      <aff id="A21">
        <label>21</label>
        <addr-line content-type="verbatim">CIBIO, Centro de Investigação em Biodiversidade e Recursos Genéticos, InBIO Laboratório Associado, Universidade do Porto, Campus de Vairão, Vairão 4485-661, Portugal</addr-line>
        <institution>CIBIO, Centro de Investigação em Biodiversidade e Recursos Genéticos, InBIO Laboratório Associado, Universidade do Porto</institution>
        <addr-line content-type="city">Vairão</addr-line>
        <country>Portugal</country>
      </aff>
      <aff id="A22">
        <label>22</label>
        <addr-line content-type="verbatim">BIOPOLIS Program in Genomics, Biodiversity and Land Planning, CIBIO, Vairão 4485-661, Portugal</addr-line>
        <institution>BIOPOLIS Program in Genomics, Biodiversity and Land Planning, CIBIO</institution>
        <addr-line content-type="city">Vairão</addr-line>
        <country>Portugal</country>
      </aff>
      <aff id="A23">
        <label>23</label>
        <addr-line content-type="verbatim">Fundação Kissama, Rua 60 Casa 560, Lar do Patriota, Luanda, Angola</addr-line>
        <institution>Fundação Kissama</institution>
        <addr-line content-type="city">Luanda</addr-line>
        <country>Angola</country>
      </aff>
      <aff id="A24">
        <label>24</label>
        <addr-line content-type="verbatim">Institut National de Recherche en Sciences Exactes et Naturelles, Brazzaville, Congo</addr-line>
        <institution>Institut National de Recherche en Sciences Exactes et Naturelles</institution>
        <addr-line content-type="city">Brazzaville</addr-line>
        <country>Congo</country>
      </aff>
      <aff id="A25">
        <label>25</label>
        <addr-line content-type="verbatim">Department of Natural History, New Brunswick Museum, Saint John, Canada</addr-line>
        <institution>Department of Natural History, New Brunswick Museum</institution>
        <addr-line content-type="city">Saint John</addr-line>
        <country>Canada</country>
        <uri content-type="ror">https://ror.org/010ja5431</uri>
      </aff>
      <author-notes>
        <fn fn-type="corresp">
          <p>Corresponding author: Javier Lobón-Rovira (<email xlink:type="simple">j.lobon.rovira@hotmail.com</email>)</p>
        </fn>
        <fn>
          <p><bold>Editors</bold> Christopher Burridge</p>
        </fn>
      </author-notes>
      <pub-date pub-type="collection">
        <year>2026</year>
      </pub-date>
      <pub-date pub-type="epub">
        <day>29</day>
        <month>09</month>
        <year>2026</year>
      </pub-date>
      <volume>19</volume>
      <elocation-id>e195124</elocation-id>
      <uri content-type="arpha" xlink:href="http://openbiodiv.net/D8F7D075-19EB-5296-9587-48A3CD7D5CB5">D8F7D075-19EB-5296-9587-48A3CD7D5CB5</uri>
      <history>
        <date date-type="received">
          <day>10</day>
          <month>04</month>
          <year>2026</year>
        </date>
        <date date-type="accepted">
          <day>14</day>
          <month>09</month>
          <year>2026</year>
        </date>
      </history>
      <permissions>
        <copyright-statement>Javier Lobón-Rovira, Edmund W. Basham, Vaclav Gvozdik, Eli Greenbaum, Gabriel Badjedjea, Abraham Bamba-Kaya, Patrick S. Champagne, Brittany A. Dobbins, Chifundera Kusamba, Simon P. Loader, John V. Lyakurwa, Marcel T. Kouete, Franck M. Masudi, Michele Menegon, Tadeáš Nečas, Johannes Penner, Mark-Oliver Rödel, Elie Tobi, Krystal A. Tolley, Pedro Vaz Pinto, Ange-Ghislain Zassi-Boulou, Magali Zoungrana, Gregory F. M. Jongsma</copyright-statement>
        <license license-type="creative-commons-attribution" xlink:href="http://creativecommons.org/licenses/by/4.0/" xlink:type="simple">
          <license-p>This is an open access article distributed under the terms of the Creative Commons Attribution License (CC BY 4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.</license-p>
        </license>
      </permissions>
      <abstract>
        <label>Abstract</label>
        <p>The genus <italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadoboa">Dipsadoboa</tp:taxon-name-part></tp:taxon-name></italic> (<tp:taxon-name><tp:taxon-name-part taxon-name-part-type="family" reg="Colubridae">Colubridae</tp:taxon-name-part></tp:taxon-name>) is a widely distributed group of arboreal snakes encompassing 13 recognized species across sub-Saharan Africa. Despite its ecological significance and the availability of specimens, its phylogenetic relationships and biogeographic history remain poorly resolved. This study presents the most comprehensive phylogenetic and biogeographic analysis of <italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadoboa">Dipsadoboa</tp:taxon-name-part></tp:taxon-name></italic> to date, using mitochondrial data (<italic><abbrev xlink:title="16S ribosomal RNA">16S</abbrev></italic>, <italic><abbrev xlink:title="cytochrome b">Cyt-b</abbrev></italic>, and <italic><abbrev xlink:title="NADH dehydrogenase subunit 4">ND4</abbrev></italic>) representing all recognized taxa. Species delimitation analyses reveal cryptic genetic diversity and highlight taxa requiring further investigation. Divergence time estimates suggest that <italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadoboa">Dipsadoboa</tp:taxon-name-part></tp:taxon-name></italic> originated in East Africa during the early Miocene (~22 Mya), with subsequent radiations across forested regions of sub-Saharan Africa. Biogeographic reconstructions support founder-event speciation combined with vicariance driven by forest fluctuations and Rift Valley formation. This resulted in multiple independent colonizations of Upper Guinean Forests and structured genetic lineages across the range of the genus. The results identify the Guineo-Congolian forest region as a major diversity hotspot, while East Africa likely served as the center of origin. Altogether, this study provides a robust framework for future integrative taxonomic, evolutionary, and conservation research on <italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadoboa">Dipsadoboa</tp:taxon-name-part></tp:taxon-name></italic>, facilitating accurate species delimitation, improved assessments of species distributions, and a better understanding of evolutionary history, all of which are essential for informing conservation priorities and management strategies in understudied regions of Africa.</p>
        <sec sec-type="Highlights" id="sec1">
          <title>Highlights</title>
          <boxed-text position="float">
            <list list-type="bullet">
              <list-item>
                <p>The first comprehensive phylogenetic framework for the African snake genus <italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadoboa">Dipsadoboa</tp:taxon-name-part></tp:taxon-name></italic>.</p>
              </list-item>
              <list-item>
                <p>Species delimitation analyses suggest substantial cryptic diversity across the genus.</p>
              </list-item>
              <list-item>
                <p><italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadoboa">Dipsadoboa</tp:taxon-name-part></tp:taxon-name></italic> most likely originated in East Africa during the early Miocene.</p>
              </list-item>
              <list-item>
                <p>The Lower Guinean Forest in the Congo Basin represents the main diversity hotspot.</p>
              </list-item>
              <list-item>
                <p>Dispersal, climatic refugia, and Rift Valley formation jointly shaped diversification of the genus.</p>
              </list-item>
            </list>
          </boxed-text>
        </sec>
      </abstract>
      <kwd-group>
        <label>Keywords</label>
        <kwd>Africa</kwd>
        <kwd>ancestral reconstruction</kwd>
        <kwd>BioGeoBEARS</kwd>
        <kwd>colubrids</kwd>
        <kwd>
          <tp:taxon-name>
            <tp:taxon-name-part taxon-name-part-type="subfamily" reg="Colubrinae">Colubrinae</tp:taxon-name-part>
          </tp:taxon-name>
        </kwd>
        <kwd>phylogeography</kwd>
        <kwd>systematics</kwd>
        <kwd>time-calibrated tree</kwd>
      </kwd-group>
      <funding-group>
        <funding-statement>JLR is Juan de la Cierva Grant from the Spanish Government under Grant JDC2024-053262-I. EB was funded by the Stengl-Wyer Fellowship and the Biodiversity Center at the University of Texas at Austin. Fieldwork by EG in DRC and subsequent laboratory work at UTEP was funded by the Percy Sladen Memorial Fund, an IUCN/SSC Amphibian Specialist Group Seed Grant, K. Reed, M.D., research funds from the Department of Biology at Villanova University, two National Geographic Research and Exploration Grants (nos. 8556-08 and WW-R018-17), a University of Texas System Rising STARs Award, UTEP, the Conservation, Food &amp; Health Foundation, and the US National Science Foundation (DEB-1145459). EG thanks Ana Betancourt of the Border Biomedical Research Center (BBRC) Genomics Analysis Core Facility for services and facilities provided. We thank the the Museu De História Natural de Maputo for logistical assistance with permitting and permissions in Mozambique (nos. 129/DPAN/2014, 507/DPAZ/SPFFB/420/2014, 315/MNH/E27/2014, 08/2018, 282/DPTADERZ/GD/SPFFB/420, 730/DPTADER/NPL/REP, 1090/DPTADER/SPFFB/600 ), the National Geographic Society Committee for Research and Exploration (CRE 9281-13), the South African National Biodiversity Institute, and the National Research Foundation of South Africa (Grant #92776) for providing funding and Khangela Safaris for logistical support for the Mozambique survey. This work was supported by Grant 5U54MD007592 from the National Institute on Minority Health and Health Disparities (NIMHD), a component of the US National Institutes of Health (NIH). Research contributions by VG and TN were supported by the Czech Science Foundation (23-07331S), and VG also by the Ministry of Culture of the Czech Republic (DRKOV 2024–2028/6.l.c, National Museum of the Czech Republic, 00023272).</funding-statement>
      </funding-group>
    </article-meta>
  </front>
  <body>
    <sec sec-type="Introduction" id="sec2">
      <title>Introduction</title>
      <p>The diversity of some African vertebrates has been profoundly impacted by the biogeographic history of this continent (e.g., <xref ref-type="bibr" rid="B25">Kelly et al. 2009</xref>; <xref ref-type="bibr" rid="B1">Allen et al. 2021</xref>; <xref ref-type="bibr" rid="B69">Tolley and Alexander 2025</xref>). Global cooling and the associated expansion of savannas and climatic refugia, together with the formation of the East African Rift and broader African uplift, have been identified as major drivers of diversification during the Miocene (<xref ref-type="bibr" rid="B48">Plana 2004</xref>; <xref ref-type="bibr" rid="B13">Couvreur et al. 2021</xref>). These geological and climatic events have also been proposed as major determinants of African biogeographic structure, shaping barriers and dispersal corridors that influenced species distributions across the continent (<xref ref-type="bibr" rid="B13">Couvreur et al. 2021</xref>). Collectively, they contributed to the differentiation of the major biogeographic regions currently recognized across East, West, Central, and Southern Africa, as well as to the distinct patterns of species diversity observed between them.</p>
      <p>Among African vertebrates, reptiles remain one of the least-studied groups (<xref ref-type="bibr" rid="B14">Cox et al. 2022</xref>). This knowledge gap has serious implications for the understanding of their species diversity and the prioritization of areas of high species richness under an increasingly changing environment (<xref ref-type="bibr" rid="B75">Wang and Yoder 2025</xref>). Efforts have been made to document the conservation status of African species (<xref ref-type="bibr" rid="B68">Tolley et al. 2016</xref>; <xref ref-type="bibr" rid="B14">Cox et al. 2022</xref>), but the continent still harbors a high number of data-deficient species. Research efforts are unevenly distributed across reptile groups. Snakes remain among the least-studied taxa, largely because of their elusive behavior and, in many cases, substantial morphological conservatism and complex biogeographic patterns that confound taxonomic resolution (<xref ref-type="bibr" rid="B25">Kelly et al. 2009</xref>; <xref ref-type="bibr" rid="B1">Allen et al. 2021</xref>; <xref ref-type="bibr" rid="B69">Tolley and Alexander 2025</xref>). Furthermore, Africa‘s complex biogeographic history has produced evolutionary patterns that include both widespread species and narrowly endemic species within the same genera (<xref ref-type="bibr" rid="B15">Dagallier et al. 2020</xref>). Consequently, accurately delimiting species diversity and reconstructing their evolutionary histories are essential steps toward developing informed and effective conservation strategies (<xref ref-type="bibr" rid="B39">Mace 2004</xref>; <xref ref-type="bibr" rid="B65">Sandall et al. 2023</xref>).</p>
      <p><italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadoboa">Dipsadoboa</tp:taxon-name-part></tp:taxon-name></italic> is a genus of arboreal colubrine snakes (<tp:taxon-name><tp:taxon-name-part taxon-name-part-type="family" reg="Colubridae">Colubridae</tp:taxon-name-part></tp:taxon-name>: <tp:taxon-name><tp:taxon-name-part taxon-name-part-type="subfamily" reg="Colubrinae">Colubrinae</tp:taxon-name-part></tp:taxon-name>) distributed across sub-Saharan Africa, from Senegal east to the Great Rift Valley and south to South Africa. It represents a group of snakes that specialize in consuming lizards, frogs, and frog eggs (<xref ref-type="bibr" rid="B57">Rasmussen 1986</xref>; <xref ref-type="bibr" rid="B3">Badjedjea et al. 2025</xref>). Currently, the genus includes 13 recognized species and several subspecies (<xref ref-type="bibr" rid="B28">Laurent 1951</xref>, <xref ref-type="bibr" rid="B29">1956</xref>; <xref ref-type="bibr" rid="B57">Rasmussen 1986</xref>, <xref ref-type="bibr" rid="B58">1989a</xref>, <xref ref-type="bibr" rid="B59">1989b</xref>, <xref ref-type="bibr" rid="B60">1993</xref>; <xref ref-type="bibr" rid="B8">Branch et al. 2019</xref>; <xref ref-type="bibr" rid="B71">Trape et al. 2023</xref>; <xref ref-type="bibr" rid="B11">Conradie et al. 2026</xref>), primarily distributed throughout closed-canopy habitats, including rainforests and moist woodland savannas. In contrast to other snake groups, <italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadoboa">Dipsadoboa</tp:taxon-name-part></tp:taxon-name></italic> species are commonly encountered, with large numbers of specimens available in museum collections and represented in online repositories (&gt;1,500 records in <xref ref-type="bibr" rid="B23">GBIF 2026</xref>, <ext-link xlink:href="https://www.gbif.org" ext-link-type="uri">https://www.gbif.org</ext-link>; <xref ref-type="bibr" rid="B73">Uetz et al. 2024</xref>). The abundance of records has enabled detailed morphological revisions, primarily conducted by Laurent (<xref ref-type="bibr" rid="B28">1951</xref>, <xref ref-type="bibr" rid="B29">1956</xref>) and Rasmussen (<xref ref-type="bibr" rid="B57">1986</xref>, <xref ref-type="bibr" rid="B58">1989a</xref>, <xref ref-type="bibr" rid="B59">1989b</xref>, <xref ref-type="bibr" rid="B60">1993</xref>). However, most species and subspecies have not yet been assessed in a phylogenetic framework, limiting confidence in the current taxonomy based only on morphological traits (<xref ref-type="bibr" rid="B8">Branch et al. 2019</xref>; <xref ref-type="bibr" rid="B71">Trape et al. 2023</xref>; <xref ref-type="bibr" rid="B11">Conradie et al. 2026</xref>). Therefore, evaluation of species boundaries in <italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadoboa">Dipsadoboa</tp:taxon-name-part></tp:taxon-name></italic> within a phylogenetic context can allow more robust taxonomic inferences (i.e., hypotheses) to be made and further evaluated using a fully integrative taxonomic pipeline (<xref ref-type="bibr" rid="B47">Padial et al. 2010</xref>) as more supporting data become available. However, there is a lack of genetically validated records for <italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadoboa">Dipsadoboa</tp:taxon-name-part></tp:taxon-name></italic>, as extensive morphological conservatism among taxa has resulted in recurrent cases of taxonomic misidentification and uncertainty regarding species boundaries (e.g., <xref ref-type="bibr" rid="B60">Rasmussen 1993</xref>; <xref ref-type="bibr" rid="B64">Sánchez-Vialas et al. 2022</xref>; <xref ref-type="bibr" rid="B11">Conradie et al. 2026</xref>). Misidentification not only compromises taxonomic decision-making but may also lead to erroneous interpretations of species distributions and evolutionary patterns, thereby hindering accurate assessments of conservation status.</p>
      <p>Morphologically, the genus <italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadoboa">Dipsadoboa</tp:taxon-name-part></tp:taxon-name></italic> has been addressed by several authors (<xref ref-type="bibr" rid="B29">Laurent 1956</xref>; <xref ref-type="bibr" rid="B9">Broadley and Stevens 1971</xref>; <xref ref-type="bibr" rid="B57">Rasmussen 1986</xref>, <xref ref-type="bibr" rid="B58">1989a</xref>, <xref ref-type="bibr" rid="B59">1989b</xref>; <xref ref-type="bibr" rid="B70">Trape and Baldé 2014</xref>; <xref ref-type="bibr" rid="B8">Branch et al. 2019</xref>; <xref ref-type="bibr" rid="B71">Trape et al. 2023</xref>), but only <xref ref-type="bibr" rid="B60">Rasmussen (1993)</xref> provided a detailed revision and synthesis of the genus. In that work, <xref ref-type="bibr" rid="B60">Rasmussen (1993)</xref> structured the genus <italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadoboa">Dipsadoboa</tp:taxon-name-part></tp:taxon-name></italic> into four major species groups based on morphology: (1) the ‘aulica’ group, including <italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadoboa">D.</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="species" reg="aulica">aulica</tp:taxon-name-part></tp:taxon-name></italic> (Günther, 1864), <italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadoboa">D.</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="species" reg="flavida">flavida</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="subspecies" reg="flavida">flavida</tp:taxon-name-part></tp:taxon-name></italic> (Broadley &amp; Stevens, 1971), and <italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadoboa">D.</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="species" reg="flavida">f.</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="subspecies" reg="broadleyi">broadleyi</tp:taxon-name-part></tp:taxon-name></italic> Rasmussen, 1989; (2) the ‘<italic>duchesnii</italic>’ group (spelled “<tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadoboa"/><tp:taxon-name-part taxon-name-part-type="species">duchesnei</tp:taxon-name-part></tp:taxon-name>” in error by <xref ref-type="bibr" rid="B59">Rasmussen (1989b)</xref>), including <italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadoboa">D.</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="species" reg="duchesnii">duchesnii</tp:taxon-name-part></tp:taxon-name></italic> (Boulenger, 1901) and <italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadomorphus">D.</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="species" reg="brevirostris">brevirostris</tp:taxon-name-part></tp:taxon-name></italic> (Sternfeld, 1908); (3) the ‘<tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadoboa"/><tp:taxon-name-part taxon-name-part-type="species">unicolor</tp:taxon-name-part></tp:taxon-name>’ group, including <italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadoboa">D.</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="species" reg="unicolor">unicolor</tp:taxon-name-part></tp:taxon-name></italic> Günther, 1858 (Rasmussen placed <italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadoboa">D.</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="species" reg="unicolor">unicolor</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="subspecies" reg="viridiventris">viridiventris</tp:taxon-name-part></tp:taxon-name></italic> Laurent, 1956 in the synonymy of <italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadoboa">D.</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="species" reg="unicolor">unicolor</tp:taxon-name-part></tp:taxon-name></italic> based on the morphological overlap between the two taxa), <italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadoboa">D.</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="species" reg="underwoodi">underwoodi</tp:taxon-name-part></tp:taxon-name></italic> Rasmussen, 1993, <italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadomorphus">D.</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="species" reg="viridis">viridis</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="subspecies" reg="viridis">viridis</tp:taxon-name-part></tp:taxon-name></italic> (Peters, 1869), <italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadomorphus">D.</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="species" reg="viridis">viridis</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="subspecies" reg="gracilis">gracilis</tp:taxon-name-part></tp:taxon-name></italic> Laurent, 1956, and <italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadophidium">D.</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="species" reg="weileri">weileri</tp:taxon-name-part></tp:taxon-name></italic> (Lindholm, 1905); and (4) the ‘<italic>werneri</italic>’ group, including <italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadoboa">D.</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="species" reg="werneri">werneri</tp:taxon-name-part></tp:taxon-name></italic> (Boulenger, 1897), <italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadoboa">D.</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="species" reg="shrevei">shrevei</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="subspecies" reg="shrevei">shrevei</tp:taxon-name-part></tp:taxon-name></italic> (Loveridge, 1932), and <italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadoboa">D.</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="species" reg="shrevei">shrevei</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="subspecies" reg="kageleri">kageleri</tp:taxon-name-part></tp:taxon-name></italic> Uthmöller, 1939.</p>
      <p>Since then, a few taxonomic changes have occurred. <xref ref-type="bibr" rid="B70">Trape and Baldé (2014)</xref> regarded <italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadomorphus">D.</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="species" reg="brevirostris">brevirostris</tp:taxon-name-part></tp:taxon-name></italic> as a junior synonym of <italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadoboa">D.</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="species" reg="duchesnii">duchesnii</tp:taxon-name-part></tp:taxon-name></italic> and resurrected <italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadomorphus">D.</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="species" reg="guineensis">guineensis</tp:taxon-name-part></tp:taxon-name></italic> (Chabanaud, 1920) and, based on morphological data, elevated it to species level. Previously, it had sometimes been treated as the subspecies <italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadomorphus">D.</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="species" reg="duchesnii">duchesnii</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="subspecies" reg="guineensis">guineensis</tp:taxon-name-part></tp:taxon-name></italic> (e.g., <xref ref-type="bibr" rid="B35">Loveridge 1941</xref>; <xref ref-type="bibr" rid="B29">Laurent 1956</xref>), and it was later synonymized with <italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadomorphus">D.</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="species" reg="brevirostris">brevirostris</tp:taxon-name-part></tp:taxon-name></italic> (<xref ref-type="bibr" rid="B59">Rasmussen 1989b</xref>). Subsequently, <xref ref-type="bibr" rid="B8">Branch et al. (2019)</xref>, using mitochondrial <italic><abbrev xlink:title="cytochrome b">Cyt-b</abbrev></italic> sequences, provided the first phylogenetic hypothesis for the genus. In that study, the authors described a new species, <italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadoboa">D.</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="species" reg="montisilva">montisilva</tp:taxon-name-part></tp:taxon-name></italic> Branch, Conradie &amp; Tolley, 2019, from the ‘sky islands’ of Mozambique, as being sister to <italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadoboa">D.</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="species" reg="werneri">werneri</tp:taxon-name-part></tp:taxon-name></italic>. <xref ref-type="bibr" rid="B8">Branch et al. (2019)</xref> also proposed the elevation of <italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadoboa">D.</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="species" reg="shrevei">shrevei</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="subspecies" reg="kageleri">kageleri</tp:taxon-name-part></tp:taxon-name></italic> to full species status as <italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadoboa">D.</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="species" reg="kageleri">kageleri</tp:taxon-name-part></tp:taxon-name></italic>. Later, <xref ref-type="bibr" rid="B71">Trape et al. (2023)</xref> described <italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadoboa">D.</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="species" reg="riparia">riparia</tp:taxon-name-part></tp:taxon-name></italic> Trape, Mediannikov &amp; Baldé, 2023, corresponding to the previous Upper Guinean populations of <italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadophidium">D.</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="species" reg="weileri">weileri</tp:taxon-name-part></tp:taxon-name></italic>, revalidated <italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadoboa">D.</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="species" reg="unicolor">unicolor</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="subspecies" reg="viridiventris">viridiventris</tp:taxon-name-part></tp:taxon-name></italic>, and stated that this taxon likely constitutes a distinct species; they also presented a new phylogenetic hypothesis based on mitochondrial <italic><abbrev xlink:title="16S ribosomal RNA">16S</abbrev></italic> rRNA data. Finally, <xref ref-type="bibr" rid="B11">Conradie et al. (2026)</xref>, building on the preliminary results of <xref ref-type="bibr" rid="B8">Branch et al. (2019)</xref> and incorporating newly available material from the type localities of <italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadoboa">D.</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="species" reg="flavida">f.</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="subspecies" reg="flavida">flavida</tp:taxon-name-part></tp:taxon-name></italic> and <italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadoboa">D.</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="species" reg="flavida">f.</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="subspecies" reg="broadleyi">broadleyi</tp:taxon-name-part></tp:taxon-name></italic>, synonymized the latter taxon with the former. Despite these advances in the systematics and taxonomy of the genus, several taxa have not been incorporated into a phylogenetic context. This is especially relevant for certain groups in which (i) allopatric populations within species are known to exist (e.g., <italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadoboa">D.</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="species" reg="underwoodi">underwoodi</tp:taxon-name-part></tp:taxon-name></italic>, <italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadoboa">D.</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="species" reg="unicolor">unicolor</tp:taxon-name-part></tp:taxon-name></italic>, and <italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadoboa">D.</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="species" reg="werneri">werneri</tp:taxon-name-part></tp:taxon-name></italic>) and whose taxonomic status remains unresolved (<xref ref-type="bibr" rid="B58">Rasmussen 1989a</xref>, <xref ref-type="bibr" rid="B60">1993</xref>), as well as for (ii) other widely distributed taxa (e.g., <italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadomorphus">D.</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="species" reg="viridis">viridis</tp:taxon-name-part></tp:taxon-name></italic>) with recognized subspecies that have never been genetically tested (<xref ref-type="bibr" rid="B29">Laurent 1956</xref>; <xref ref-type="bibr" rid="B60">Rasmussen 1993</xref>).</p>
      <p>Resolving the uncertainty regarding the taxonomic status of <italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadoboa">Dipsadoboa</tp:taxon-name-part></tp:taxon-name></italic> species and their evolutionary relationships has the potential to provide an excellent model for testing evolutionary patterns through time on the African continent. This is because of their wide distribution across the continent and their predominantly arboreal lifestyle, which link them to forest environments. Specifically, the genus could be an excellent group for assessing the role of climatic changes in influencing speciation patterns and present-day species richness patterns. In this context, the major geological and climatic processes outlined above provide explicit expectations for the evolutionary history of <italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadoboa">Dipsadoboa</tp:taxon-name-part></tp:taxon-name></italic>, particularly regarding its geographic origin, the direction and frequency of dispersal among African biogeographic regions, and the timing of diversification within the major forest blocks. These biogeographic questions motivated <xref ref-type="bibr" rid="B60">Rasmussen (1993)</xref> to explore the evolutionary biogeography of the genus, identifying the Lower Guinean Forests, spanning from southern Nigeria through Cameroon, Equatorial Guinea, Gabon, and parts of the Republic of the Congo (<xref ref-type="bibr" rid="B76">White 1979</xref>) as the center of diversity of the genus (region II; <italic>fide</italic><xref ref-type="bibr" rid="B60">Rasmussen 1993</xref>: 189), with up to six species reported from this region (<italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadomorphus">D.</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="species" reg="brevirostris">brevirostris</tp:taxon-name-part></tp:taxon-name></italic>, <italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadoboa">D.</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="species" reg="duchesnii">duchesnii</tp:taxon-name-part></tp:taxon-name></italic>, <italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadoboa">D.</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="species" reg="unicolor">unicolor</tp:taxon-name-part></tp:taxon-name></italic>, <italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadoboa">D.</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="species" reg="underwoodi">underwoodi</tp:taxon-name-part></tp:taxon-name></italic>, <italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadomorphus">D.</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="species" reg="viridis">viridis</tp:taxon-name-part></tp:taxon-name></italic>, and <italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadophidium">D.</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="species" reg="weileri">weileri</tp:taxon-name-part></tp:taxon-name></italic>); however, the validity of <italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadomorphus">D.</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="species" reg="brevirostris">brevirostris</tp:taxon-name-part></tp:taxon-name></italic> was later disputed (<xref ref-type="bibr" rid="B70">Trape and Baldé 2014</xref>). Based on a cladistic analysis of morphological characters, <xref ref-type="bibr" rid="B60">Rasmussen (1993)</xref> proposed a widespread ancestral distribution across sub-Saharan Africa. He also noted that an East African origin was supported by the presence of the sister genus <italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Crotaphopeltis">Crotaphopeltis</tp:taxon-name-part></tp:taxon-name></italic> in that region (<xref ref-type="bibr" rid="B60">Rasmussen 1993</xref>; <xref ref-type="bibr" rid="B17">Engelbrecht et al. 2021</xref>). Together with the broader geological and climatic processes outlined above, these previous hypotheses provide explicit predictions that can be tested within a temporal biogeographic framework. Specifically, an East African origin would predict an ancestral range in this region followed by dispersal toward Central and West Africa; the occurrence of multiple West African lineages could result from either a single colonization followed by <italic>in situ</italic> diversification or multiple independent dispersal events from Central Africa; and, if climatic fluctuations were important drivers of diversification, major cladogenetic events within Central African forests would be expected to broadly coincide with Miocene climatic shifts and associated forest fragmentation.</p>
      <p>Here, the taxonomic status of <italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadoboa">Dipsadoboa</tp:taxon-name-part></tp:taxon-name></italic> species is assessed, and the biogeography of the genus is evaluated by reassessing previous biogeographic and taxonomic hypotheses using comprehensive geographic and taxonomic sampling across the entire range of the genus. This allowed the following questions to be addressed: (i) How do the morphological groups proposed by <xref ref-type="bibr" rid="B60">Rasmussen (1993)</xref> align with the phylogenetic structure revealed by mitochondrial DNA data? (ii) What is the extent of genetic diversity between and within species in the genus? (iii) What are the main biogeographical patterns underlying the distribution and origin of the genus? and (iv) Which evolutionary processes have driven speciation in this group? To achieve this, samples from across Africa encompassing the distribution of all recognized taxa were compiled. The analyses were based on three mitochondrial DNA markers (<italic><abbrev xlink:title="16S ribosomal RNA">16S</abbrev></italic>, <italic><abbrev xlink:title="cytochrome b">Cyt-b</abbrev></italic>, and <italic><abbrev xlink:title="NADH dehydrogenase subunit 4">ND4</abbrev></italic>). By combining genetic data, species delimitation models, and geographic distribution information, Rasmussen’s biogeographical hypotheses were tested, mitochondrial lineage boundaries were assessed, the presence of potential cryptic diversity within the genus was evaluated, and a scenario for the origin and evolutionary history of <italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadoboa">Dipsadoboa</tp:taxon-name-part></tp:taxon-name></italic> was proposed. Specifically, the dated phylogeny and ancestral-range reconstructions allowed evaluation of the timing and direction of diversification in relation to the major geological and climatic processes proposed to have shaped African biogeography.</p>
    </sec>
    <sec sec-type="materials|methods" id="sec3">
      <title>Materials and methods</title>
      <sec sec-type="Sampling and genetic data" id="sec4">
        <title>Sampling and genetic data</title>
        <p><italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadoboa">Dipsadoboa</tp:taxon-name-part></tp:taxon-name></italic> tissue samples obtained through fieldwork and loans from museum collections were processed, and mitochondrial DNA (<abbrev xlink:title="mitochondrial DNA">mtDNA</abbrev>) was analyzed. The samples represented all recognized species and covered the known distributional range of the genus across sub-Saharan Africa. Information on tissue samples and their associated voucher specimens, where available, is provided in Suppl. material <xref ref-type="supplementary-material" rid="S1">1</xref>: table S1. Additionally, sequences of <italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadoboa">Dipsadoboa</tp:taxon-name-part></tp:taxon-name></italic> were retrieved from GenBank to complement the newly generated dataset. In total, the final dataset comprised new genetic material from 152 <italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadoboa">Dipsadoboa</tp:taxon-name-part></tp:taxon-name></italic> samples plus 39 sequences from GenBank. The outgroup included multiple sequences and species from 25 colubrid genera (Suppl. material <xref ref-type="supplementary-material" rid="S1">1</xref>: table S2). To leverage available <italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadoboa">Dipsadoboa</tp:taxon-name-part></tp:taxon-name></italic> data from GenBank and complement previous phylogenetic work on the group, data were generated for three mitochondrial markers (<abbrev xlink:title="16S ribosomal RNA">16S</abbrev> ribosomal RNA [<italic><abbrev xlink:title="16S ribosomal RNA">16S</abbrev></italic>], cytochrome b [<italic><abbrev xlink:title="cytochrome b">Cyt-b</abbrev></italic>], and NADH dehydrogenase subunit 4 [<italic><abbrev xlink:title="NADH dehydrogenase subunit 4">ND4</abbrev></italic>], including flanking transfer RNAs [<abbrev xlink:title="transfer RNAs">tRNAs</abbrev>]; Suppl. material <xref ref-type="supplementary-material" rid="S1">1</xref>: table S2). DNA was extracted using commercial DNA extraction kits following the manufacturers’ protocols. Primer sequences and polymerase chain reaction (<abbrev xlink:title="polymerase chain reaction">PCR</abbrev>) conditions are listed in Suppl. material <xref ref-type="supplementary-material" rid="S1">1</xref>: table S3. Raw sequences were checked and edited using Geneious Prime v. 2024.0.5 (<ext-link xlink:href="http://www.geneious.com/" ext-link-type="uri">http://www.geneious.com/</ext-link>) and aligned using the MUSCLE plugin for Geneious Prime. All new sequences have been deposited in GenBank (Suppl. material <xref ref-type="supplementary-material" rid="S1">1</xref>: table S2).</p>
      </sec>
      <sec sec-type="Phylogenetic analyses" id="sec5">
        <title>Phylogenetic analyses</title>
        <p>Phylogenetic relationships were inferred using both maximum likelihood (<abbrev xlink:title="maximum likelihood">ML</abbrev>) and Bayesian inference (<abbrev xlink:title="Bayesian inference">BI</abbrev>) approaches for the concatenated dataset of all three loci (<italic><abbrev xlink:title="16S ribosomal RNA">16S</abbrev></italic>, <italic><abbrev xlink:title="cytochrome b">Cyt-b</abbrev></italic>, and <italic><abbrev xlink:title="NADH dehydrogenase subunit 4">ND4</abbrev></italic>; 2,227 bp). The <abbrev xlink:title="maximum likelihood">ML</abbrev> analysis was also run for each locus separately to produce individual gene trees. The <abbrev xlink:title="maximum likelihood">ML</abbrev> analyses were performed in IQ-TREE v. 2.3.4 (<xref ref-type="bibr" rid="B72">Trifinopoulos et al. 2016</xref>). For the concatenated dataset, three partitions were used, and 1,000 bootstrap replicates were run with the ultrafast bootstrap approximation method (<xref ref-type="bibr" rid="B24">Hoang et al. 2018</xref>). The best-fitting substitution models were selected automatically for each partition. Bootstrap support (<abbrev xlink:title="Bootstrap support">BS</abbrev>) values of 95% or higher were considered to provide strong support (<xref ref-type="bibr" rid="B42">Minh et al. 2013</xref>). For Bayesian inference, MrBayes v. 3.2.7 (<xref ref-type="bibr" rid="B63">Ronquist et al. 2012</xref>) was used with the concatenated dataset divided into three partitions. The <abbrev xlink:title="Bayesian inference">BI</abbrev> analysis ran for 10 × 10<sup>6</sup> generations using Metropolis-coupled Markov chain Monte Carlo (<abbrev xlink:title="Markov chain Monte Carlo">MCMC</abbrev>), sampling every 1,000 generations. Convergence and effective sample sizes (<abbrev xlink:title="effective sample sizes">ESS</abbrev> &gt; 200) were assessed in TRACER v. 1.7.2 (<xref ref-type="bibr" rid="B56">Rambaut et al. 2018</xref>). A 25% burn-in was discarded, and a 50% majority-rule consensus tree was generated in MrBayes. The substitution model space was set with the parameters <italic>lset nst=mixed rates=invgamma</italic>, and posterior probabilities (<abbrev xlink:title="posterior probabilities">PP</abbrev>) ≥ 0.95 were considered to indicate strong support.</p>
      </sec>
      <sec sec-type="Species delimitation" id="sec6">
        <title>Species delimitation</title>
        <p>Given the uncertainty surrounding genetic boundaries among putative taxa (species or subspecies) and the limitations of relying exclusively on mitochondrial DNA (<xref ref-type="bibr" rid="B77">Wüster 2025</xref>), multiple species delimitation approaches were applied to infer the most reliable species limits. These alternative delimitation schemes were subsequently used in the biogeographic analyses.</p>
        <p>Species delimitation was inferred for both <italic><abbrev xlink:title="16S ribosomal RNA">16S</abbrev></italic> [430 bp] and <italic><abbrev xlink:title="cytochrome b">Cyt-b</abbrev></italic> [1,020 bp] using the ASAP and ABGD methods (<xref ref-type="bibr" rid="B53">Puillandre et al. 2012</xref>, <xref ref-type="bibr" rid="B52">2021</xref>). Pairwise sequence divergences based on current taxonomy were estimated using SpeciesIdentifier v. 1.8 (<xref ref-type="bibr" rid="B43">Meier et al. 2006</xref>) to generate frequency distributions of intra- and interspecific sequence divergence for the <italic><abbrev xlink:title="cytochrome b">Cyt-b</abbrev></italic> gene. Because this analysis cannot accommodate missing data, the leading and trailing ends of the sequences were trimmed to 650 bp, and seven sequences were removed entirely because of their short reads (one each of <italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadoboa">D.</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="species" reg="montisilva">montisilva</tp:taxon-name-part></tp:taxon-name></italic>, <italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadoboa">D.</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="species" reg="unicolor">u.</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="subspecies" reg="viridiventris">viridiventris</tp:taxon-name-part></tp:taxon-name></italic>, and <italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadoboa">D.</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="species" reg="werneri">werneri</tp:taxon-name-part></tp:taxon-name></italic>; two each of <italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadoboa">D.</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="species" reg="underwoodi">underwoodi</tp:taxon-name-part></tp:taxon-name></italic> and <italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadophidium">D.</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="species" reg="weileri">weileri</tp:taxon-name-part></tp:taxon-name></italic>). Given that genetic divergences are expected to be low within species but high between species, intraspecific and interspecific divergence values were expected not to overlap (the ‘barcode gap’; <xref ref-type="bibr" rid="B43">Meier et al. 2006</xref>).</p>
        <p>The divergence threshold separating intra- from interspecific comparisons provides an initial guideline for species delimitation (<xref ref-type="bibr" rid="B31">Lefébure et al. 2006</xref>). To complement the SpeciesIdentifier analyses, individuals were assigned to putative species based on <italic><abbrev xlink:title="cytochrome b">Cyt-b</abbrev></italic> ASAP and ABGD results, as well as currently recognized taxa, to evaluate their taxonomic validity (16 taxa in total). All species of <italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadoboa">Dipsadoboa</tp:taxon-name-part></tp:taxon-name></italic> were included, except <italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadoboa">D.</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="species" reg="riparia">riparia</tp:taxon-name-part></tp:taxon-name></italic>, for which <italic><abbrev xlink:title="cytochrome b">Cyt-b</abbrev></italic> data are unavailable. Finally, net uncorrected pairwise sequence divergences (<italic>p</italic>-distances) were estimated separately for <italic><abbrev xlink:title="16S ribosomal RNA">16S</abbrev></italic> [430 bp] and <italic><abbrev xlink:title="cytochrome b">Cyt-b</abbrev></italic> [650 bp] in MEGA v. 10.1.7 (<xref ref-type="bibr" rid="B26">Kumar et al. 2018</xref>) to quantify intra- and interspecific variation among strongly divergent mitochondrial lineages. To reduce analytical uncertainty and facilitate comparison between analyses, the same trimmed datasets as in SpeciesIdentifier were used. This enabled direct comparison of interspecific divergence values across species within the genus, including the focal taxa, with the frequency distributions obtained from SpeciesIdentifier.</p>
      </sec>
      <sec sec-type="Divergence time estimation" id="sec7">
        <title>Divergence time estimation</title>
        <p>The genus <italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadoboa">Dipsadoboa</tp:taxon-name-part></tp:taxon-name></italic> is sister to <italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Crotaphopeltis">Crotaphopeltis</tp:taxon-name-part></tp:taxon-name></italic> and belongs to the subfamily <tp:taxon-name><tp:taxon-name-part taxon-name-part-type="subfamily" reg="Colubrinae">Colubrinae</tp:taxon-name-part></tp:taxon-name> (<xref ref-type="bibr" rid="B79">Zaher et al. 2019</xref>). More specifically, <italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadoboa">Dipsadoboa</tp:taxon-name-part></tp:taxon-name></italic> is assigned to the clade referred to as “<tp:taxon-name><tp:taxon-name-part taxon-name-part-type="subfamily" reg="Colubrinae">Colubrinae</tp:taxon-name-part></tp:taxon-name> 2” <italic>sensu</italic><xref ref-type="bibr" rid="B80">Zheng and Wiens (2016)</xref>, which includes several African genera. The divergence time from <italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Crotaphopeltis">Crotaphopeltis</tp:taxon-name-part></tp:taxon-name></italic> was previously addressed by <xref ref-type="bibr" rid="B17">Engelbrecht et al. (2021)</xref>, and therefore, the timing of lineage diversification within <italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadoboa">Dipsadoboa</tp:taxon-name-part></tp:taxon-name></italic> was estimated using the same fossil calibration points and protocol defined by these authors (Suppl. material <xref ref-type="supplementary-material" rid="S1">1</xref>: table S2). Accordingly, a time-calibrated gene tree was estimated in BEAST v. 2.6.3, as specified below. Newly generated sequences for <italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadoboa">Dipsadoboa</tp:taxon-name-part></tp:taxon-name></italic> were combined with additional sequences obtained from GenBank, resulting in a concatenated dataset partitioned by gene.</p>
        <p>Once congruence between the time-calibrated tree topology of <xref ref-type="bibr" rid="B17">Engelbrecht et al. (2021)</xref> and the concatenated dataset was corroborated (Suppl. material <xref ref-type="supplementary-material" rid="S1">1</xref>: fig. S1), secondary calibration points were applied to a pruned dataset (selected target species, including all <italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadoboa">Dipsadoboa</tp:taxon-name-part></tp:taxon-name></italic> species identified by the species delimitation analyses and <italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Crotaphopeltis">Crotaphopeltis</tp:taxon-name-part></tp:taxon-name></italic> as the outgroup) to reduce missing data and avoid unrealistic age estimates. Best-fit substitution models were obtained using the <italic>bModelTest</italic> package implemented in BEAST 2 (<xref ref-type="bibr" rid="B6">Bouckaert and Drummond 2017</xref>). An uncorrelated lognormal clock prior was selected for the three genes. For each gene partition, among-site rate heterogeneity was modeled using a gamma distribution with four rate categories. A birth–death speciation process was specified as the tree prior, with random starting trees. Calibration priors were constructed using normal distributions, with mean and sigma values adjusted so that the distributions matched the 95% credible intervals reported in the primary study, as follows: (C1) the divergence between <italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Crotaphopeltis">Crotaphopeltis</tp:taxon-name-part></tp:taxon-name></italic> and <italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadoboa">Dipsadoboa</tp:taxon-name-part></tp:taxon-name></italic>, estimated at 21–29 million years ago (Mya) (mean = 25.0 Mya, SD = 2.5 Mya; 95% CI: 20.9–29.1 Mya), and (C2) the divergence between <italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Crotaphopeltis">Crotaphopeltis</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="species" reg="degeni">degeni</tp:taxon-name-part></tp:taxon-name></italic> and <italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Crotaphopeltis">C.</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="species" reg="tornieri">tornieri</tp:taxon-name-part></tp:taxon-name></italic> 1, estimated at 9–16 Mya (mean = 12 Mya, SD = 1.8 Mya; 95% CI: 9.4–15.0 Mya). Uninformative priors (gamma distribution with parameters α = 0.1 and β = 10) were assigned to the molecular clock parameters, which were estimated during the analysis. Ten independent <abbrev xlink:title="Markov chain Monte Carlo">MCMC</abbrev> runs were conducted, each for 200 million generations and sampled every 10,000 generations. Convergence and adequate sampling were assessed in TRACER v. 1.7.2, and the first 10% of samples were discarded as burn-in. Post-burn-in trees from all runs were combined using LogCombiner v. 2.3.0, and a maximum clade credibility (<abbrev xlink:title="maximum clade credibility">MCC</abbrev>) chronogram was generated in TreeAnnotator v. 1.8. The resulting dated phylogeny was visualized in FigTree (<xref ref-type="bibr" rid="B55">Rambaut 2009</xref>).</p>
      </sec>
      <sec sec-type="Biogeographic analysis" id="sec8">
        <title>Biogeographic analysis</title>
        <p>Historical range evolution and biogeographic origins of <italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadoboa">Dipsadoboa</tp:taxon-name-part></tp:taxon-name></italic> were reconstructed using the BioGeoBEARS package in R v. 4.4.0 (<xref ref-type="bibr" rid="B54">R Core Team 2021</xref>). The time-calibrated <abbrev xlink:title="maximum clade credibility">MCC</abbrev> tree was pruned to retain only ingroup taxa. Because some nodes received low support, the topology at these nodes was considered unresolved, and they were collapsed to account for phylogenetic uncertainty. The present distribution of <italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadoboa">Dipsadoboa</tp:taxon-name-part></tp:taxon-name></italic> was divided into four major regions, reflecting environmental and geological features across sub-Saharan Africa, but extending from East Africa southward to middle Mozambique following the Rift Valley division. Three regions correspond to the major Afrotropical forest subdivisions recognized by <xref ref-type="bibr" rid="B32">Linder et al. (2012)</xref> and <xref ref-type="bibr" rid="B12">Couvreur et al. (2008)</xref>: (i) the Guineo-Congolian forests (the Congolian Region of <xref ref-type="bibr" rid="B32">Linder et al. 2012</xref>), encompassing the Lower Guinean forests and the Congo Basin and extending from Nigeria eastward to Uganda and southward to Angola; (ii) the Upper Guinean forests (Guinean Region of <xref ref-type="bibr" rid="B32">Linder et al. 2012</xref>), extending from Senegal to Togo; and (iii) the Eastern Afromontane forests, comprising forested areas east of the eastern branch of the African Rift System, from Mozambique to Kenya. An additional region was delineated to represent the moist savannas and woodlands described by <xref ref-type="bibr" rid="B66">Sayre et al. (2013)</xref> and treated as a major bioregion (the Zambezi Region) by <xref ref-type="bibr" rid="B32">Linder et al. (2012)</xref>. This region is referred to here as (iv) the Southern Savannas and includes the Miombo and mixed woodlands located south of the Congo Basin and west of the Malawi Rift. This regionalization allows not only the geographic origin of the genus, as proposed by <xref ref-type="bibr" rid="B60">Rasmussen (1993)</xref>, to be tested but also the assessment of whether the evolutionary origin of the group is associated primarily with closed-canopy forest habitats or with more open moist savanna and woodland ecosystems. The maximum allowed range size was set to three regions. Ancestral range estimation was conducted under the Dispersal–Extinction–Cladogenesis model (<abbrev xlink:title="Dispersal–Extinction–Cladogenesis model">DEC</abbrev>; <xref ref-type="bibr" rid="B61">Ree and Smith 2008</xref>), which accounts for vicariance and ‘subset’ sympatric speciation; DIVALIKE (<xref ref-type="bibr" rid="B62">Ronquist 1997</xref>), which accounts for vicariance; and BAYAREALIKE (<xref ref-type="bibr" rid="B27">Landis et al. 2013</xref>), which accounts for widespread sympatric speciation but not vicariance. All models were implemented with the +J parameter, allowing for founder-event speciation and providing adequate statistical comparison in situations in which most species have geographic ranges restricted to single areas (<xref ref-type="bibr" rid="B38">Matzke 2022</xref>).</p>
        <p>As the taxonomy of this group remains partially unresolved, the results of the ASAP and ABGD analyses of the <italic><abbrev xlink:title="cytochrome b">Cyt-b</abbrev></italic> dataset were selected as the most conservative and reliable. Thus, the 14 clusters, plus <italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadoboa">D.</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="species" reg="riparia">riparia</tp:taxon-name-part></tp:taxon-name></italic> (not available in the <italic><abbrev xlink:title="cytochrome b">Cyt-b</abbrev></italic> dataset) and the nominal taxa <italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadomorphus">D.</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="species" reg="brevirostris">brevirostris</tp:taxon-name-part></tp:taxon-name></italic> and <italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadomorphus">D.</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="species" reg="guineensis">guineensis</tp:taxon-name-part></tp:taxon-name></italic>, assigned according to the proximity of the type localities, were used. This resulted in 17 tips for the time-calibrated tree and biogeographic reconstruction.</p>
      </sec>
    </sec>
    <sec sec-type="Results" id="sec9">
      <title>Results</title>
      <sec sec-type="Phylogenetic analyses" id="sec10">
        <title>Phylogenetic analyses</title>
        <p>All phylogenetic trees estimated from individual genes using maximum likelihood (<abbrev xlink:title="maximum likelihood">ML</abbrev>) and Bayesian inference (<abbrev xlink:title="Bayesian inference">BI</abbrev>) analyses showed topologies similar to those of the concatenated analyses (Fig. <xref ref-type="fig" rid="F1">1</xref>), although minor differences were detected between the <italic><abbrev xlink:title="cytochrome b">Cyt-b</abbrev></italic> and <italic><abbrev xlink:title="NADH dehydrogenase subunit 4">ND4</abbrev></italic> mitochondrial gene trees and the <italic><abbrev xlink:title="16S ribosomal RNA">16S</abbrev></italic> phylogenetic reconstruction (Suppl. material <xref ref-type="supplementary-material" rid="S1">1</xref>: figs S1, S2); the latter was poorly supported at most nodes (Suppl. material <xref ref-type="supplementary-material" rid="S1">1</xref>: fig. S2), in agreement with the proposal that the use of <italic><abbrev xlink:title="16S ribosomal RNA">16S</abbrev></italic> for phylogenetic reconstructions in squamates should be viewed with caution and may be misleading (<xref ref-type="bibr" rid="B36">Main et al. 2024</xref>). In all analyses, the monophyly of the genus was strongly supported (<abbrev xlink:title="Bootstrap support">BS</abbrev> = 100 / <abbrev xlink:title="posterior probabilities">PP</abbrev> = 1), and it was recovered as sister to the genus <italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Crotaphopeltis">Crotaphopeltis</tp:taxon-name-part></tp:taxon-name></italic> (Fig. <xref ref-type="fig" rid="F1">1</xref>, Suppl. material <xref ref-type="supplementary-material" rid="S1">1</xref>: fig. S3). All phylogenetic analyses recovered four major well-supported clades and one deeply divergent lineage corresponding to <italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadoboa">D.</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="species" reg="kageleri">kageleri</tp:taxon-name-part></tp:taxon-name></italic>. The ASAP and ABGD analyses recovered 14 clusters in the <italic><abbrev xlink:title="cytochrome b">Cyt-b</abbrev></italic> dataset (excluding <italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadoboa">D.</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="species" reg="riparia">riparia</tp:taxon-name-part></tp:taxon-name></italic>, which was not available in <italic><abbrev xlink:title="cytochrome b">Cyt-b</abbrev></italic>) and 18 clusters in the <italic><abbrev xlink:title="16S ribosomal RNA">16S</abbrev></italic> dataset (excluding <italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadoboa">D.</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="species" reg="kageleri">kageleri</tp:taxon-name-part></tp:taxon-name></italic> and <italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadoboa">D.</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="species" reg="werneri">werneri</tp:taxon-name-part></tp:taxon-name></italic>, which were not available in <italic><abbrev xlink:title="16S ribosomal RNA">16S</abbrev></italic>; Fig. <xref ref-type="fig" rid="F1">1</xref>). The results from the <italic><abbrev xlink:title="cytochrome b">Cyt-b</abbrev></italic> dataset are consistent with the frequency histogram of sequence divergences generated in SpeciesIdentifier, which indicates that values &gt; 8% correspond to interspecific divergence (Fig. <xref ref-type="fig" rid="F2">2</xref>). The frequency histogram of sequence divergences did not show a distinct “barcode gap,” but instead showed an area of overlap between inter- and intraspecific values in the range of 4–5%. This overlap, however, was attributed only to <italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadoboa">D.</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="species" reg="duchesnii">duchesnii</tp:taxon-name-part></tp:taxon-name></italic> and <italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadomorphus">D.</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="species" reg="brevirostris">brevirostris</tp:taxon-name-part></tp:taxon-name></italic>/<italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadomorphus">D.</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="species" reg="guineensis">guineensis</tp:taxon-name-part></tp:taxon-name></italic>, which had sequence divergences that fell within the intraspecific range (Fig. <xref ref-type="fig" rid="F2">2</xref>). A “gray zone” in the intraspecific region between 5% and 8% was ascribed to the pronounced genetic structure of <italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadoboa">D.</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="species" reg="montisilva">montisilva</tp:taxon-name-part></tp:taxon-name></italic>, <italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadoboa">D.</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="species" reg="shrevei">shrevei</tp:taxon-name-part></tp:taxon-name></italic>, <italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadomorphus">D.</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="species" reg="viridis">viridis</tp:taxon-name-part></tp:taxon-name></italic>, and <italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadophidium">D.</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="species" reg="weileri">weileri</tp:taxon-name-part></tp:taxon-name></italic> (Fig. <xref ref-type="fig" rid="F2">2</xref>). Among the interspecific comparisons, the lower range (e.g., 8.5–9.5%) can be attributed to <italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadoboa">D.</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="species" reg="underwoodi">underwoodi</tp:taxon-name-part></tp:taxon-name></italic> vs. <tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadoboa">D.</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="uncertainty-rank">cf.</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="species" reg="underwoodi">underwoodi</tp:taxon-name-part></tp:taxon-name> and <italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadoboa">D.</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="species" reg="unicolor">unicolor</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="subspecies" reg="viridiventris">viridiventris</tp:taxon-name-part></tp:taxon-name></italic> vs. <italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadophidium">D.</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="species" reg="weileri">weileri</tp:taxon-name-part></tp:taxon-name></italic>. Importantly, both approaches (i.e., ASAP and the <italic>p</italic>-distance frequency distributions) suggest that <italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadoboa">D.</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="species" reg="duchesnii">duchesnii</tp:taxon-name-part></tp:taxon-name></italic>, <italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadomorphus">D.</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="species" reg="brevirostris">brevirostris</tp:taxon-name-part></tp:taxon-name></italic>, and <italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadomorphus">D.</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="species" reg="guineensis">guineensis</tp:taxon-name-part></tp:taxon-name></italic> are conspecific, although this hypothesis requires additional validation (Figs <xref ref-type="fig" rid="F1">1</xref>, <xref ref-type="fig" rid="F2">2</xref>).</p>
        <fig id="F1">
          <object-id content-type="doi">10.21425/fob.19.195124.figure1</object-id>
          <object-id content-type="arpha">899415E6-C9ED-5F99-B01F-073116650C4E</object-id>
          <label>Figure 1.</label>
          <caption>
            <p>The maximum likelihood (<abbrev xlink:title="maximum likelihood">ML</abbrev>) topology for <italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadoboa">Dipsadoboa</tp:taxon-name-part></tp:taxon-name></italic> based on concatenated mitochondrial data, with <abbrev xlink:title="maximum likelihood">ML</abbrev> bootstrap and Bayesian inference (<abbrev xlink:title="Bayesian inference">BI</abbrev>) support values indicated at each node and coded according to the key. The phylogeny is split into two panels, as shown in the inset at the top left. Species delimitation results are indicated in the right panel, with species groupings color-coded for each method (ASAP for the <italic><abbrev xlink:title="16S ribosomal RNA">16S</abbrev></italic> gene, ABGD for the <italic><abbrev xlink:title="16S ribosomal RNA">16S</abbrev></italic> gene, ASAP for the <italic><abbrev xlink:title="cytochrome b">Cyt-b</abbrev></italic> gene, and ABGD for the <italic><abbrev xlink:title="cytochrome b">Cyt-b</abbrev></italic> gene).</p>
          </caption>
          <graphic xlink:href="biogeography-19-001_article-195124__-g001.jpg" id="oo_1793691.jpg">
            <uri content-type="original_file">https://binary.pensoft.net/fig/1793691</uri>
          </graphic>
        </fig>
        <fig id="F2">
          <object-id content-type="doi">10.21425/fob.19.195124.figure2</object-id>
          <object-id content-type="arpha">5A9E75BD-C4D9-588F-B4E5-42F30A6B0C90</object-id>
          <label>Figure 2.</label>
          <caption>
            <p>Frequencies of <italic><abbrev xlink:title="cytochrome b">Cyt-b</abbrev></italic> pairwise sequence divergence values among and within <italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadoboa">Dipsadoboa</tp:taxon-name-part></tp:taxon-name></italic> based on the existing taxonomy. Interspecific distances are shown by black bars, and intraspecific distances are shown by gray bars. Red shading shows the range for <italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadoboa">D.</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="species" reg="duchesnii">duchesnii</tp:taxon-name-part></tp:taxon-name></italic> and <italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadomorphus">D.</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="species" reg="guineensis">guineensis</tp:taxon-name-part></tp:taxon-name></italic>/<italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadomorphus">D.</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="species" reg="brevirostris">brevirostris</tp:taxon-name-part></tp:taxon-name></italic>, and gray shading shows the range attributed to pairwise distances among <italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadoboa">D.</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="species" reg="montisilva">montisilva</tp:taxon-name-part></tp:taxon-name></italic>, <italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadoboa">D.</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="species" reg="shrevei">shrevei</tp:taxon-name-part></tp:taxon-name></italic>, <italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadomorphus">D.</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="species" reg="viridis">viridis</tp:taxon-name-part></tp:taxon-name></italic>, and <italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadophidium">D.</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="species" reg="weileri">weileri</tp:taxon-name-part></tp:taxon-name></italic>, forming the “gray zone.”</p>
          </caption>
          <graphic xlink:href="biogeography-19-001_article-195124__-g002.jpg" id="oo_1793692.jpg">
            <uri content-type="original_file">https://binary.pensoft.net/fig/1793692</uri>
          </graphic>
        </fig>
        <p>The basal node strongly supports (<abbrev xlink:title="Bootstrap support">BS</abbrev> = 100 / <abbrev xlink:title="posterior probabilities">PP</abbrev> = 0.99) the monophyly of the genus <italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadoboa">Dipsadoboa</tp:taxon-name-part></tp:taxon-name></italic>, while the first clade—sister to all other <italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadoboa">Dipsadoboa</tp:taxon-name-part></tp:taxon-name></italic> and containing the ‘<italic>aulica</italic>’ group and the deeply divergent <italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadoboa">D.</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="species" reg="kageleri">kageleri</tp:taxon-name-part></tp:taxon-name></italic>—is not strongly supported (<abbrev xlink:title="Bootstrap support">BS</abbrev> = 68 / <abbrev xlink:title="posterior probabilities">PP</abbrev> = 0.64; Fig. <xref ref-type="fig" rid="F1">1</xref>). Within the ‘<italic>aulica</italic>’ group, two mitochondrial lineages were identified (<italic><abbrev xlink:title="cytochrome b">Cyt-b</abbrev></italic> net uncorrected <italic>p</italic>-distance 12.9%; Suppl. material <xref ref-type="supplementary-material" rid="S1">1</xref>: table S4), corresponding to the nominal <italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadoboa">D.</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="species" reg="aulica">aulica</tp:taxon-name-part></tp:taxon-name></italic> and <italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadoboa">D.</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="species" reg="flavida">flavida</tp:taxon-name-part></tp:taxon-name></italic> from the eastern region of South Africa, Mozambique, and Tanzania, respectively, on the southern and northern banks of the Zambezi River (Figs <xref ref-type="fig" rid="F1">1</xref>, <xref ref-type="fig" rid="F3">3</xref>). The monophyly of both <italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadoboa">D.</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="species" reg="aulica">aulica</tp:taxon-name-part></tp:taxon-name></italic> and <italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadoboa">D.</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="species" reg="flavida">flavida</tp:taxon-name-part></tp:taxon-name></italic> was highly supported (<abbrev xlink:title="Bootstrap support">BS</abbrev> = 100 / <abbrev xlink:title="posterior probabilities">PP</abbrev> = 1), and the two species were identified as sister species.</p>
        <fig id="F3">
          <object-id content-type="doi">10.21425/fob.19.195124.figure3</object-id>
          <object-id content-type="arpha">D43D19C2-375C-5E59-9376-0459E9167545</object-id>
          <label>Figure 3.</label>
          <caption>
            <p>Distribution of members of the <italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadoboa">Dipsadoboa</tp:taxon-name-part></tp:taxon-name></italic> ‘<italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadoboa"/><tp:taxon-name-part taxon-name-part-type="species" reg="duchesnii">duchesnii</tp:taxon-name-part></tp:taxon-name></italic>’ group (above) and ‘aulica’ group (below) on a hybrid map of the major vegetation divisions (<xref ref-type="bibr" rid="B66">Sayre et al. 2013</xref>). Different colors depict different mitochondrial lineages corresponding to those in Fig. <xref ref-type="fig" rid="F1">1</xref>. See the inset for an explanation of the colors. Stars depict type localities. Black dots represent genetically tested samples. Red stars indicate the original localities of <italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadoboa">D.</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="species" reg="duchesnii">duchesnii</tp:taxon-name-part></tp:taxon-name></italic> syntypes.</p>
          </caption>
          <graphic xlink:href="biogeography-19-001_article-195124__-g003.jpg" id="oo_1793693.jpg">
            <uri content-type="original_file">https://binary.pensoft.net/fig/1793693</uri>
          </graphic>
        </fig>
        <p>The remaining species are divided into three major clades. The ‘<italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadoboa"/><tp:taxon-name-part taxon-name-part-type="species" reg="werneri">werneri</tp:taxon-name-part></tp:taxon-name></italic>’ group (<abbrev xlink:title="Bootstrap support">BS</abbrev> = 88 / <abbrev xlink:title="posterior probabilities">PP</abbrev> = 0.81; Fig. <xref ref-type="fig" rid="F1">1</xref>) includes three recognized species, <italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadoboa">D.</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="species" reg="werneri">werneri</tp:taxon-name-part></tp:taxon-name></italic>, <italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadoboa">D.</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="species" reg="montisilva">montisilva</tp:taxon-name-part></tp:taxon-name></italic>, and <italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadoboa">D.</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="species" reg="shrevei">shrevei</tp:taxon-name-part></tp:taxon-name></italic>, with &gt; 11% net uncorrected <italic>p</italic>-distance for <italic><abbrev xlink:title="cytochrome b">Cyt-b</abbrev></italic> among them (Suppl. material <xref ref-type="supplementary-material" rid="S1">1</xref>: table S4). <italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadoboa">Dipsadoboa</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="species" reg="werneri">werneri</tp:taxon-name-part></tp:taxon-name></italic> and <italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadoboa">D.</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="species" reg="montisilva">montisilva</tp:taxon-name-part></tp:taxon-name></italic> from East Africa are more closely related (<abbrev xlink:title="Bootstrap support">BS</abbrev> = 100 / <abbrev xlink:title="posterior probabilities">PP</abbrev> = 0.99), and together they form a sister clade to <italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadoboa">D.</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="species" reg="shrevei">shrevei</tp:taxon-name-part></tp:taxon-name></italic> (<abbrev xlink:title="Bootstrap support">BS</abbrev> = 100 / <abbrev xlink:title="posterior probabilities">PP</abbrev> = 0.99). The latter is distributed across the wet miombo and mixed woodlands of southern Africa (Fig. <xref ref-type="fig" rid="F4">4</xref>).</p>
        <fig id="F4">
          <object-id content-type="doi">10.21425/fob.19.195124.figure4</object-id>
          <object-id content-type="arpha">2D2545DD-FF24-5B50-A66F-8E177A54ACAF</object-id>
          <label>Figure 4.</label>
          <caption>
            <p>Distribution of members of the <italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadoboa">Dipsadoboa</tp:taxon-name-part></tp:taxon-name></italic> ‘<tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadoboa"/><tp:taxon-name-part taxon-name-part-type="species">unicolor</tp:taxon-name-part></tp:taxon-name>’ group (<italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadoboa">D.</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="species" reg="underwoodi">underwoodi</tp:taxon-name-part></tp:taxon-name></italic> subclade; above) and ‘<italic>werneri</italic>’ group (below) on a hybrid map of the major vegetation divisions (<xref ref-type="bibr" rid="B66">Sayre et al. 2013</xref>). Different colors depict different mitochondrial lineages corresponding to those in Fig. <xref ref-type="fig" rid="F1">1</xref>. See the inset for an explanation of the colors. Stars depict type localities. Black dots represent genetically tested samples.</p>
          </caption>
          <graphic xlink:href="biogeography-19-001_article-195124__-g004.jpg" id="oo_1793694.jpg">
            <uri content-type="original_file">https://binary.pensoft.net/fig/1793694</uri>
          </graphic>
        </fig>
        <p>The phylogenetic reconstruction recovered the ‘<italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadoboa"/><tp:taxon-name-part taxon-name-part-type="species" reg="duchesnii">duchesnii</tp:taxon-name-part></tp:taxon-name></italic>’ clade as a sister group to the ‘<tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadoboa"/><tp:taxon-name-part taxon-name-part-type="species">unicolor</tp:taxon-name-part></tp:taxon-name>’ group with moderate support (<abbrev xlink:title="Bootstrap support">BS</abbrev> = 87 / <abbrev xlink:title="posterior probabilities">PP</abbrev> = 0.81) and included all members of the ‘<italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadoboa"/><tp:taxon-name-part taxon-name-part-type="species" reg="duchesnii">duchesnii</tp:taxon-name-part></tp:taxon-name></italic>’ group: <italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadoboa">D.</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="species" reg="duchesnii">duchesnii</tp:taxon-name-part></tp:taxon-name></italic>, <italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadomorphus">D.</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="species" reg="brevirostris">brevirostris</tp:taxon-name-part></tp:taxon-name></italic>, and <italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadomorphus">D.</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="species" reg="guineensis">guineensis</tp:taxon-name-part></tp:taxon-name></italic>. However, all phylogenetic reconstructions recovered four mitochondrial lineages, including these taxa, with low genetic divergence among them for <italic><abbrev xlink:title="cytochrome b">Cyt-b</abbrev></italic> (net uncorrected <italic>p</italic>-distance &lt; 5.0%; Suppl. material <xref ref-type="supplementary-material" rid="S1">1</xref>: table S4), within the intraspecific threshold indicated by SpeciesIdentifier (Fig. <xref ref-type="fig" rid="F2">2</xref>). Furthermore, the analysis recovered <italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadomorphus">D.</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="species" reg="brevirostris">brevirostris</tp:taxon-name-part></tp:taxon-name></italic> from southeastern Nigeria (near the type locality in southwestern Cameroon) and <italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadomorphus">D.</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="species" reg="guineensis">guineensis</tp:taxon-name-part></tp:taxon-name></italic> from Guinea and Liberia as sister taxa, and together they form a clade that is sister to <italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadoboa">D.</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="species" reg="duchesnii">duchesnii</tp:taxon-name-part></tp:taxon-name></italic> (Figs <xref ref-type="fig" rid="F1">1</xref>, <xref ref-type="fig" rid="F3">3</xref>).</p>
        <p>The ‘<tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadoboa"/><tp:taxon-name-part taxon-name-part-type="species">unicolor</tp:taxon-name-part></tp:taxon-name>’ major group recovered the ‘<tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadoboa"/><tp:taxon-name-part taxon-name-part-type="species">underwoodi</tp:taxon-name-part></tp:taxon-name>’ clade, morphologically a member of the ‘<tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadoboa"/><tp:taxon-name-part taxon-name-part-type="species">unicolor</tp:taxon-name-part></tp:taxon-name>’ group, as a well-resolved clade sister to the other members of the ‘<tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadoboa"/><tp:taxon-name-part taxon-name-part-type="species">unicolor</tp:taxon-name-part></tp:taxon-name>’ group (<abbrev xlink:title="Bootstrap support">BS</abbrev> = 100 / <abbrev xlink:title="posterior probabilities">PP</abbrev> = 0.94; &gt; 15% <italic><abbrev xlink:title="cytochrome b">Cyt-b</abbrev></italic> net uncorrected <italic>p</italic>-distance from all other members of the group). This clade comprises two highly divergent mitochondrial lineages (<italic><abbrev xlink:title="cytochrome b">Cyt-b</abbrev></italic> net uncorrected <italic>p</italic>-distance 8.1%; Suppl. material <xref ref-type="supplementary-material" rid="S1">1</xref>: table S4), including the nominal <italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadoboa">D.</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="species" reg="underwoodi">underwoodi</tp:taxon-name-part></tp:taxon-name></italic>, which is documented from the western Congolian and eastern Lower Guinean forests, and a second lineage named herein as <tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadoboa">D.</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="uncertainty-rank">cf.</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="species" reg="underwoodi">underwoodi</tp:taxon-name-part></tp:taxon-name>, genetically documented from the Upper Guinean forests (Figs <xref ref-type="fig" rid="F1">1</xref>, <xref ref-type="fig" rid="F4">4</xref>). Finally, a large clade including all the remaining members of the ‘<tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadoboa"/><tp:taxon-name-part taxon-name-part-type="species">unicolor</tp:taxon-name-part></tp:taxon-name>’ group (<abbrev xlink:title="Bootstrap support">BS</abbrev> = 99 / <abbrev xlink:title="posterior probabilities">PP</abbrev> = 0.91) was recovered with two well-defined subclades (<italic><abbrev xlink:title="cytochrome b">Cyt-b</abbrev></italic> net uncorrected <italic>p</italic>-distance &gt; 10% between clades; Figs <xref ref-type="fig" rid="F1">1</xref>, <xref ref-type="fig" rid="F5">5</xref>; Suppl. material <xref ref-type="supplementary-material" rid="S1">1</xref>: table S4). The first clade includes the nominotypical <italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadoboa">D.</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="species" reg="unicolor">unicolor</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="subspecies" reg="unicolor">unicolor</tp:taxon-name-part></tp:taxon-name></italic> from the Upper Guinean forests and <italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadomorphus">D.</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="species" reg="viridis">viridis</tp:taxon-name-part></tp:taxon-name></italic> (<abbrev xlink:title="Bootstrap support">BS</abbrev> = 96 / <abbrev xlink:title="posterior probabilities">PP</abbrev> = 1) from West and Central Africa, which have a large genetic divergence between them (<italic><abbrev xlink:title="cytochrome b">Cyt-b</abbrev></italic> net uncorrected <italic>p</italic>-distance 11.4%; Suppl. material <xref ref-type="supplementary-material" rid="S1">1</xref>: table S4). The lineage ascribed to <italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadomorphus">D.</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="species" reg="unicolor">u.</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="subspecies" reg="unicolor">unicolor</tp:taxon-name-part></tp:taxon-name></italic> includes material from Guinea and Liberia, showing low intraspecific genetic divergence. In contrast, <italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadomorphus">D.</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="species" reg="viridis">viridis</tp:taxon-name-part></tp:taxon-name></italic> exhibits pronounced genetic structuring across its distribution, with five mitochondrial lineages showing some biogeographic structure (Figs <xref ref-type="fig" rid="F1">1</xref>, <xref ref-type="fig" rid="F5">5</xref>). One of these lineages is attributed herein to the recognized subspecies <italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadoboa">D.</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="species" reg="viridis">v.</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="subspecies" reg="gracilis">gracilis</tp:taxon-name-part></tp:taxon-name></italic> from the eastern and central Congo Basin (Figs <xref ref-type="fig" rid="F1">1</xref>, <xref ref-type="fig" rid="F5">5</xref>).</p>
        <fig id="F5">
          <object-id content-type="doi">10.21425/fob.19.195124.figure5</object-id>
          <object-id content-type="arpha">B236D49E-7451-5888-9D9C-7413175E20F1</object-id>
          <label>Figure 5.</label>
          <caption>
            <p>Distribution of members of the <italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadoboa">Dipsadoboa</tp:taxon-name-part></tp:taxon-name></italic> ‘<tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadoboa"/><tp:taxon-name-part taxon-name-part-type="species">unicolor</tp:taxon-name-part></tp:taxon-name>’ group (excluding the <italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadoboa">D.</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="species" reg="underwoodi">underwoodi</tp:taxon-name-part></tp:taxon-name></italic> subclade included in Fig. <xref ref-type="fig" rid="F4">4</xref>) on a hybrid map of the major vegetation divisions (<xref ref-type="bibr" rid="B66">Sayre et al. 2013</xref>). Different colors depict different mitochondrial lineages corresponding to those in Fig. <xref ref-type="fig" rid="F1">1</xref>. See the inset for an explanation of the colors. Stars depict type localities. Black dots represent genetically tested samples.</p>
          </caption>
          <graphic xlink:href="biogeography-19-001_article-195124__-g005.jpg" id="oo_1793695.jpg">
            <uri content-type="original_file">https://binary.pensoft.net/fig/1793695</uri>
          </graphic>
        </fig>
        <p>The third clade within the ‘<tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadoboa"/><tp:taxon-name-part taxon-name-part-type="species">unicolor</tp:taxon-name-part></tp:taxon-name>’ group represents the least-resolved clade in the study. It includes three recognized taxa (<italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadophidium">D.</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="species" reg="weileri">weileri</tp:taxon-name-part></tp:taxon-name></italic>, <italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadoboa">D.</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="species" reg="unicolor">u.</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="subspecies" reg="viridiventris">viridiventris</tp:taxon-name-part></tp:taxon-name></italic>, and <italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadoboa">D.</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="species" reg="riparia">riparia</tp:taxon-name-part></tp:taxon-name></italic>), as well as one additional mitochondrial lineage previously assigned by <xref ref-type="bibr" rid="B20">Figueroa et al. (2016)</xref> and later reanalyzed by <xref ref-type="bibr" rid="B8">Branch et al. (2019)</xref> as <italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadophidium">D.</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="species" reg="weileri">weileri</tp:taxon-name-part></tp:taxon-name></italic> and by <xref ref-type="bibr" rid="B71">Trape et al. (2023)</xref> as “<tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadophidium">D.</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="uncertainty-rank">aff.</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="species" reg="weileri">weileri</tp:taxon-name-part></tp:taxon-name>,” but here referred to as <italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadoboa">Dipsadoboa</tp:taxon-name-part></tp:taxon-name></italic> sp. “NG/CM” and documented from three sites along the Cameroon Volcanic Line in Nigeria and Cameroon (Figs <xref ref-type="fig" rid="F1">1</xref>, <xref ref-type="fig" rid="F5">5</xref>). However, <italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadoboa">D.</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="species" reg="riparia">riparia</tp:taxon-name-part></tp:taxon-name></italic> formed a long branch embedded within <italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadoboa">D.</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="species" reg="unicolor">u.</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="subspecies" reg="viridiventris">viridiventris</tp:taxon-name-part></tp:taxon-name></italic>, and this common clade received only moderate support (Fig. <xref ref-type="fig" rid="F1">1</xref>). Notably, <italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadoboa">D.</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="species" reg="riparia">riparia</tp:taxon-name-part></tp:taxon-name></italic> is the only species for which only <italic><abbrev xlink:title="16S ribosomal RNA">16S</abbrev></italic> genetic data are available. The other three taxa diverged from each other by &gt; 9% net uncorrected <italic>p</italic>-distance for <italic><abbrev xlink:title="cytochrome b">Cyt-b</abbrev></italic> (Suppl. material <xref ref-type="supplementary-material" rid="S1">1</xref>: table S4).</p>
        <p>Although all described taxa were highly or moderately supported as monophyletic clades, <italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadoboa">D.</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="species" reg="unicolor">unicolor</tp:taxon-name-part></tp:taxon-name></italic> was the only species recovered as paraphyletic. The nominotypical subspecies, <italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadomorphus">D.</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="species" reg="unicolor">u.</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="subspecies" reg="unicolor">unicolor</tp:taxon-name-part></tp:taxon-name></italic> from the Upper Guinean forests, was strongly supported as sister to <italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadomorphus">D.</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="species" reg="viridis">viridis</tp:taxon-name-part></tp:taxon-name></italic>, including sympatric individuals from Liberia, whereas <italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadoboa">D.</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="species" reg="unicolor">unicolor</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="subspecies" reg="viridiventris">viridiventris</tp:taxon-name-part></tp:taxon-name></italic> from the Albertine Rift was recovered as closely related to the Upper Guinean <italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadoboa">D.</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="species" reg="riparia">riparia</tp:taxon-name-part></tp:taxon-name></italic>, with both taxa forming a clade that is sister to the Central African <italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadophidium">D.</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="species" reg="weileri">weileri</tp:taxon-name-part></tp:taxon-name></italic> (Figs <xref ref-type="fig" rid="F1">1</xref>, <xref ref-type="fig" rid="F5">5</xref>). These two sister clades diverged from each other by 12.05% net uncorrected <italic>p</italic>-distance for <italic><abbrev xlink:title="cytochrome b">Cyt-b</abbrev></italic> (Suppl. material <xref ref-type="supplementary-material" rid="S1">1</xref>: table S4).</p>
      </sec>
      <sec sec-type="Divergence time estimates and biogeographic history" id="sec11">
        <title>Divergence time estimates and biogeographic history</title>
        <p>The time-calibrated trees (Fig. <xref ref-type="fig" rid="F6">6</xref>, Suppl. material <xref ref-type="supplementary-material" rid="S1">1</xref>: figs S3, S4) were largely congruent with the topology inferred from the concatenated dataset, supporting the monophyly of <italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadoboa">Dipsadoboa</tp:taxon-name-part></tp:taxon-name></italic>, the four main groups, and <italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadoboa">D.</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="species" reg="kageleri">kageleri</tp:taxon-name-part></tp:taxon-name></italic> as a distinct lineage on a long branch. However, the monophyly of <italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadoboa">D.</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="species" reg="unicolor">u.</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="subspecies" reg="viridiventris">viridiventris</tp:taxon-name-part></tp:taxon-name></italic> was not supported with respect to <italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadoboa">D.</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="species" reg="riparia">riparia</tp:taxon-name-part></tp:taxon-name></italic>, and the two taxa were collapsed with their sister species <italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadophidium">D.</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="species" reg="weileri">weileri</tp:taxon-name-part></tp:taxon-name></italic> for the biogeographic analysis.</p>
        <fig id="F6">
          <object-id content-type="doi">10.21425/fob.19.195124.figure6</object-id>
          <object-id content-type="arpha">CF0CB05F-5E45-5AA5-B9BE-EE03175741E9</object-id>
          <label>Figure 6.</label>
          <caption>
            <p>Phylogeographic and geographic ancestral reconstruction of the genus <italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadoboa">Dipsadoboa</tp:taxon-name-part></tp:taxon-name></italic>. <bold>A</bold>. Time-calibrated phylogeny of <italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadoboa">Dipsadoboa</tp:taxon-name-part></tp:taxon-name></italic> with biogeographic reconstruction. Unsupported branches between <italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadoboa">D.</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="species" reg="unicolor">u.</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="subspecies" reg="viridiventris">viridiventris</tp:taxon-name-part></tp:taxon-name></italic> and <italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadoboa">D.</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="species" reg="riparia">riparia</tp:taxon-name-part></tp:taxon-name></italic> were collapsed for the analysis. Pie charts at each node indicate ancestral area probabilities, and tip squares denote species’ geographic origins. The red trend line in the background shows the deep-sea oxygen isotopic (<italic>δ</italic> 18O) record as a proxy for global temperature since the Eocene (adapted from <xref ref-type="bibr" rid="B78">Zachos et al. 2001</xref>); <bold>B</bold>. Map depicting the defined biogeographic areas and the most probable historical biogeographic scenario of <italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadoboa">Dipsadoboa</tp:taxon-name-part></tp:taxon-name></italic>. Circles indicate the likely regions of origin for the genus and its major clades. Circle sizes correspond to ancestral-to-recent nodes, from largest to smallest.</p>
          </caption>
          <graphic xlink:href="biogeography-19-001_article-195124__-g006.jpg" id="oo_1793696.jpg">
            <uri content-type="original_file">https://binary.pensoft.net/fig/1793696</uri>
          </graphic>
        </fig>
        <p>Divergence time estimates indicated that after the split of <italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadoboa">Dipsadoboa</tp:taxon-name-part></tp:taxon-name></italic> from <italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Crotaphopeltis">Crotaphopeltis</tp:taxon-name-part></tp:taxon-name></italic> (~25 Mya), diversification within the genus began in the early Miocene, approximately 22 Mya (95% highest posterior density [<abbrev xlink:title="highest posterior density">HPD</abbrev>]: 19.0–25.5 Mya; Fig. <xref ref-type="fig" rid="F6">6</xref>, Suppl. material <xref ref-type="supplementary-material" rid="S1">1</xref>: fig. S4). This initial split separated the ‘aulica’ group from the remaining lineages, although the position of <italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadoboa">D.</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="species" reg="kageleri">kageleri</tp:taxon-name-part></tp:taxon-name></italic>, which diverged during the early diversification of the genus, received lower support. Subsequently, the ‘<italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadoboa"/><tp:taxon-name-part taxon-name-part-type="species" reg="werneri">werneri</tp:taxon-name-part></tp:taxon-name></italic>’ group diverged approximately 19.5 Mya (<abbrev xlink:title="highest posterior density">HPD</abbrev>: 15.7–23.9 Mya). This was followed by the separation of the ‘<italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadoboa"/><tp:taxon-name-part taxon-name-part-type="species" reg="duchesnii">duchesnii</tp:taxon-name-part></tp:taxon-name></italic>’ group from the clade comprising the ‘<tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadoboa"/><tp:taxon-name-part taxon-name-part-type="species">unicolor</tp:taxon-name-part></tp:taxon-name>’ group at approximately 17.0 Mya (<abbrev xlink:title="highest posterior density">HPD</abbrev>: 13.0–21.2 Mya). Afterward, the ‘<tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadoboa"/><tp:taxon-name-part taxon-name-part-type="species">unicolor</tp:taxon-name-part></tp:taxon-name>’ group started to diverge approximately 14.5 Mya (<abbrev xlink:title="highest posterior density">HPD</abbrev>: 10.7–18.4 Mya), when the ‘<tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadoboa"/><tp:taxon-name-part taxon-name-part-type="species">underwoodi</tp:taxon-name-part></tp:taxon-name>’ subclade separated from the other members of the ‘<tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadoboa"/><tp:taxon-name-part taxon-name-part-type="species">unicolor</tp:taxon-name-part></tp:taxon-name>’ group. This was followed by a radiation during the mid–late Miocene of the remaining members of the ‘<tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadoboa"/><tp:taxon-name-part taxon-name-part-type="species">unicolor</tp:taxon-name-part></tp:taxon-name>’ group. Finally, the calibrated tree recovered the most recent diversification within the ‘<italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadoboa"/><tp:taxon-name-part taxon-name-part-type="species" reg="duchesnii">duchesnii</tp:taxon-name-part></tp:taxon-name></italic>’ group, occurring during the Plio-Pleistocene between ~4 and 2 Mya (Fig. <xref ref-type="fig" rid="F6">6</xref>, Suppl. material <xref ref-type="supplementary-material" rid="S1">1</xref>: fig. S4).</p>
        <p>The <abbrev xlink:title="Dispersal–Extinction–Cladogenesis model">DEC</abbrev>+J model was selected as the best-fitting biogeographic model, although DIVALIKE+J and BAYAREALIKE+J showed comparable statistical support (Table <xref ref-type="table" rid="T1">1</xref>). All biogeographic inferences are based on the <abbrev xlink:title="Dispersal–Extinction–Cladogenesis model">DEC</abbrev>+J reconstruction. According to this model, East Africa is the most probable origin of the genus <italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadoboa">Dipsadoboa</tp:taxon-name-part></tp:taxon-name></italic> (probability: 0.31), although a combined origin in southern and eastern Africa or spanning East to Central Africa cannot be entirely ruled out (probabilities: ~0.22; Fig. <xref ref-type="fig" rid="F6">6</xref>).</p>
        <table-wrap id="T1" position="float" orientation="portrait">
          <label>Table 1.</label>
          <caption>
            <p>Best-fit models for ancestral range estimation of <italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadoboa">Dipsadoboa</tp:taxon-name-part></tp:taxon-name></italic> using BioGeoBEARS, all incorporating a transition matrix. Model comparison is based on log-likelihood (<abbrev xlink:title="log-likelihood">LnL</abbrev>), the corrected Akaike information criterion (<abbrev xlink:title="Akaike information criterion">AICc</abbrev>), number of estimated parameters (<italic>n</italic>), dispersal rate (<italic>d</italic>), extinction rate (<italic>e</italic>), and the relative probability of founder-event speciation (<italic>j</italic>). The best-fitting model is highlighted in bold.</p>
          </caption>
          <table>
            <tbody>
              <tr>
                <th rowspan="1" colspan="1">
                  <bold>Model</bold>
                </th>
                <th rowspan="1" colspan="1">
                  <bold>
                    <abbrev xlink:title="log-likelihood">LnL</abbrev>
                  </bold>
                </th>
                <th rowspan="1" colspan="1">
                  <bold>n</bold>
                </th>
                <th rowspan="1" colspan="1">
                  <bold>
                    <italic>d</italic>
                  </bold>
                </th>
                <th rowspan="1" colspan="1">
                  <bold>
                    <italic>e</italic>
                  </bold>
                </th>
                <th rowspan="1" colspan="1">
                  <bold>
                    <italic>j</italic>
                  </bold>
                </th>
                <th rowspan="1" colspan="1">
                  <bold>
                    <abbrev xlink:title="Akaike information criterion">AICc</abbrev>
                  </bold>
                </th>
              </tr>
              <tr>
                <td rowspan="1" colspan="1">
                  <bold><abbrev xlink:title="Dispersal–Extinction–Cladogenesis model">DEC</abbrev>+J</bold>
                </td>
                <td rowspan="1" colspan="1">
                  <bold>–24.84</bold>
                </td>
                <td rowspan="1" colspan="1">
                  <bold>3</bold>
                </td>
                <td rowspan="1" colspan="1">
                  <bold>0.0019</bold>
                </td>
                <td rowspan="1" colspan="1">
                  <bold>1,00E-12</bold>
                </td>
                <td rowspan="1" colspan="1">
                  <bold>0.1816</bold>
                </td>
                <td rowspan="1" colspan="1">
                  <bold>57.5</bold>
                </td>
              </tr>
              <tr>
                <td rowspan="1" colspan="1">DIVALIKE+J</td>
                <td rowspan="1" colspan="1">–24.8</td>
                <td rowspan="1" colspan="1">3</td>
                <td rowspan="1" colspan="1">0.0020</td>
                <td rowspan="1" colspan="1">1,00E-12</td>
                <td rowspan="1" colspan="1">0.1743</td>
                <td rowspan="1" colspan="1">60.9</td>
              </tr>
              <tr>
                <td rowspan="1" colspan="1">BAYAREALIKE+J</td>
                <td rowspan="1" colspan="1">–24.9</td>
                <td rowspan="1" colspan="1">3</td>
                <td rowspan="1" colspan="1">0.0018</td>
                <td rowspan="1" colspan="1">1,00E-12</td>
                <td rowspan="1" colspan="1">0.1963</td>
                <td rowspan="1" colspan="1">61.1</td>
              </tr>
              <tr>
                <td rowspan="1" colspan="1">
                  <abbrev xlink:title="Dispersal–Extinction–Cladogenesis model">DEC</abbrev>
                </td>
                <td rowspan="1" colspan="1">–34.8</td>
                <td rowspan="1" colspan="1">2</td>
                <td rowspan="1" colspan="1">0.0135</td>
                <td rowspan="1" colspan="1">0.0057</td>
                <td rowspan="1" colspan="1">0</td>
                <td rowspan="1" colspan="1">74.6</td>
              </tr>
              <tr>
                <td rowspan="1" colspan="1">DIVALIKE</td>
                <td rowspan="1" colspan="1">–34.7</td>
                <td rowspan="1" colspan="1">2</td>
                <td rowspan="1" colspan="1">0.0138</td>
                <td rowspan="1" colspan="1">0.0044</td>
                <td rowspan="1" colspan="1">0</td>
                <td rowspan="1" colspan="1">77.2</td>
              </tr>
              <tr>
                <td rowspan="1" colspan="1">BAYAREALIKE</td>
                <td rowspan="1" colspan="1">–34.9</td>
                <td rowspan="1" colspan="1">2</td>
                <td rowspan="1" colspan="1">0.0135</td>
                <td rowspan="1" colspan="1">0.0057</td>
                <td rowspan="1" colspan="1">0</td>
                <td rowspan="1" colspan="1">77.6</td>
              </tr>
            </tbody>
          </table>
        </table-wrap>
        <p>Within the genus, the ‘<tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadoboa"/><tp:taxon-name-part taxon-name-part-type="species" reg="aulica">aulica</tp:taxon-name-part></tp:taxon-name>’ and ‘<italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadoboa"/><tp:taxon-name-part taxon-name-part-type="species" reg="werneri">werneri</tp:taxon-name-part></tp:taxon-name></italic>’ groups are both inferred to have originated in East Africa, with probabilities of 0.76 and 0.53, respectively (Fig. <xref ref-type="fig" rid="F6">6</xref>, Suppl. material <xref ref-type="supplementary-material" rid="S1">1</xref>: fig. S4). In contrast, the clade that includes the ‘<italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadoboa"/><tp:taxon-name-part taxon-name-part-type="species" reg="duchesnii">duchesnii</tp:taxon-name-part></tp:taxon-name></italic>’ and ‘<tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadoboa"/><tp:taxon-name-part taxon-name-part-type="species">unicolor</tp:taxon-name-part></tp:taxon-name>’ groups likely originated in the tropical forests of Central Africa (probability: 0.77; Fig. <xref ref-type="fig" rid="F6">6</xref>, Suppl. material <xref ref-type="supplementary-material" rid="S1">1</xref>: fig. S4). Biogeographic reconstructions suggest that each of these groups subsequently originated within this region and diversified along the Upper Guinean and Lower Guinean-Congolian forests. The ‘<italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadoboa"/><tp:taxon-name-part taxon-name-part-type="species" reg="duchesnii">duchesnii</tp:taxon-name-part></tp:taxon-name></italic>’ group seems to have originated in Central Africa (probability: 0.85; Fig. <xref ref-type="fig" rid="F6">6</xref>). A similar scenario was recovered for the ‘<tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadoboa"/><tp:taxon-name-part taxon-name-part-type="species">unicolor</tp:taxon-name-part></tp:taxon-name>’ group, which most likely originated within the wider Congo Basin, with a probability of ~0.70 (Fig. <xref ref-type="fig" rid="F6">6</xref>, Suppl. material <xref ref-type="supplementary-material" rid="S1">1</xref>: fig. S4). These results suggest at least three independent colonization events of the Upper Guinean forests from the Lower Guinean-Congolian forests, whereas other events driven by climatic refugia occurred within the wider Congo Basin (Fig. <xref ref-type="fig" rid="F6">6B</xref>).</p>
      </sec>
    </sec>
    <sec sec-type="Discussion" id="sec12">
      <title>Discussion</title>
      <p>African reptile systematics remains comparatively understudied relative to that in other regions of the globe, and improving knowledge of the evolutionary and biogeographic patterns of this fauna is essential for informing effective conservation strategies (<xref ref-type="bibr" rid="B5">Böhm et al. 2013</xref>; <xref ref-type="bibr" rid="B16">Deikumah et al. 2014</xref>; <xref ref-type="bibr" rid="B4">Böhm and Collen 2015</xref>; <xref ref-type="bibr" rid="B68">Tolley et al. 2016</xref>). Previously, within the family <tp:taxon-name><tp:taxon-name-part taxon-name-part-type="family" reg="Colubridae">Colubridae</tp:taxon-name-part></tp:taxon-name>, the phylogenetic position of <italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadoboa">Dipsadoboa</tp:taxon-name-part></tp:taxon-name></italic> had not been fully resolved because of limited taxon sampling and the lack of detailed analyses focused on the genus and its relatives (<xref ref-type="bibr" rid="B80">Zheng and Wiens 2016</xref>; <xref ref-type="bibr" rid="B20">Figueroa et al. 2016</xref>; <xref ref-type="bibr" rid="B79">Zaher et al. 2019</xref>). This work shows that <italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadoboa">Dipsadoboa</tp:taxon-name-part></tp:taxon-name></italic> is monophyletic and sister to <italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Crotaphopeltis">Crotaphopeltis</tp:taxon-name-part></tp:taxon-name></italic>. Furthermore, the most comprehensive phylogenetic hypothesis to date for the genus <italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadoboa">Dipsadoboa</tp:taxon-name-part></tp:taxon-name></italic> is presented. Although the phylogenetic inference relies solely on mitochondrial data and should therefore be interpreted with appropriate caution (<xref ref-type="bibr" rid="B77">Wüster 2025</xref>), the results presented here nonetheless provide an important framework and valuable baseline for future, more integrative studies of this genus, including multiple nuclear loci and morphological data. Because of the lack of data from nuclear genes, the phylogeny must be treated as a working hypothesis for a set of candidate species, against which more comprehensive datasets can be used to critically examine species boundaries.</p>
      <sec sec-type="Systematics" id="sec13">
        <title>Systematics</title>
        <p>The results recover <italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadoboa">Dipsadoboa</tp:taxon-name-part></tp:taxon-name></italic> as a monophyletic genus, sister to <italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Crotaphopeltis">Crotaphopeltis</tp:taxon-name-part></tp:taxon-name></italic>, a relationship that has been proposed in most previous phylogenetic analyses (e.g., <xref ref-type="bibr" rid="B80">Zheng and Wiens 2016</xref>; <xref ref-type="bibr" rid="B8">Branch et al. 2019</xref>; <xref ref-type="bibr" rid="B17">Engelbrecht et al. 2021</xref>; <xref ref-type="bibr" rid="B11">Conradie et al. 2026</xref>), but which contrasts with the results reported by <xref ref-type="bibr" rid="B79">Zaher et al. (2019)</xref> and <xref ref-type="bibr" rid="B71">Trape et al. (2023)</xref>, who recovered the genus as paraphyletic. These findings are consistent with the morphological distinctions between the two genera previously highlighted by <xref ref-type="bibr" rid="B28">Laurent (1951)</xref> and <xref ref-type="bibr" rid="B60">Rasmussen (1993)</xref>. Furthermore, the phylogenetic analysis partially agrees with the morphological cladogram proposed by <xref ref-type="bibr" rid="B60">Rasmussen (1993)</xref>. Notably, five major mitochondrial clades were recovered, four corresponding to the morphological clusters (<xref ref-type="bibr" rid="B60">Rasmussen 1993</xref>) of the ‘<italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadoboa"/><tp:taxon-name-part taxon-name-part-type="species" reg="aulica">aulica</tp:taxon-name-part></tp:taxon-name></italic>’, ‘<italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadoboa"/><tp:taxon-name-part taxon-name-part-type="species" reg="werneri">werneri</tp:taxon-name-part></tp:taxon-name></italic>’, ‘<italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadoboa"/><tp:taxon-name-part taxon-name-part-type="species" reg="duchesnii">duchesnii</tp:taxon-name-part></tp:taxon-name></italic>’, and ‘<tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadoboa"/><tp:taxon-name-part taxon-name-part-type="species">unicolor</tp:taxon-name-part></tp:taxon-name>’ groups, and one corresponding to the distinct <italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadoboa">D.</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="species" reg="kageleri">kageleri</tp:taxon-name-part></tp:taxon-name></italic> lineage. In contrast to <xref ref-type="bibr" rid="B60">Rasmussen (1993)</xref>, the phylogenetic placement of <italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadoboa">D.</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="species" reg="kageleri">kageleri</tp:taxon-name-part></tp:taxon-name></italic> differs from both its morphological assignment to the ‘<italic>werneri</italic>’ group and its placement in the ‘<italic>werneri</italic>’ group in a previous phylogenetic analysis, which had very low support (<xref ref-type="bibr" rid="B8">Branch et al. 2019</xref>). Instead, this species clusters within the ‘aulica’ group. Nevertheless, the node that defines its placement shows low support and should therefore be considered unresolved. Several taxonomic inconsistencies were also detected in previously published datasets, including cases of apparent misidentification (e.g., “<italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadophidium">D.</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="species" reg="weileri">weileri</tp:taxon-name-part></tp:taxon-name></italic>” or “<tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadophidium">D.</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="uncertainty-rank">aff.</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="species" reg="weileri">weileri</tp:taxon-name-part></tp:taxon-name>” MVZ 253208 in <xref ref-type="bibr" rid="B20">Figueroa et al. 2016</xref>; <xref ref-type="bibr" rid="B8">Branch et al. 2019</xref>; <xref ref-type="bibr" rid="B71">Trape et al. 2023</xref>; <xref ref-type="bibr" rid="B2">Arroyo-Lambaer et al. 2025</xref>, which is reassigned here as <italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadoboa">Dipsadoboa</tp:taxon-name-part></tp:taxon-name></italic> sp. “NG”; or “<italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadoboa">D.</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="species" reg="duchesnii">duchesnii</tp:taxon-name-part></tp:taxon-name></italic>” or “<tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadoboa">D.</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="uncertainty-rank">cf.</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="species" reg="duchesnii">duchesnii</tp:taxon-name-part></tp:taxon-name>” CAS 254086 in <xref ref-type="bibr" rid="B49">Portik et al. (2016)</xref> and <xref ref-type="bibr" rid="B71">Trape et al. (2023)</xref>, respectively, which is reidentified here as <italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadoboa">D.</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="species" reg="underwoodi">underwoodi</tp:taxon-name-part></tp:taxon-name></italic>). Based on these results, some taxonomic actions that require further investigation are proposed below (Table <xref ref-type="table" rid="T2">2</xref>).</p>
        <table-wrap id="T2" position="float" orientation="portrait">
          <label>Table 2.</label>
          <caption>
            <p>Summary of the status of <italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadoboa">Dipsadoboa</tp:taxon-name-part></tp:taxon-name></italic> taxa for each species group, based on “complexes” defined by <xref ref-type="bibr" rid="B60">Rasmussen (1993)</xref>. Species included in a phylogenetic analysis for the first time are marked with an asterisk (*). Proposed candidate species (or retained species names), based on hypotheses derived from the mitochondrial phylogeny in this study, are shown in bold in the last column (Proposed taxonomic arrangement).</p>
          </caption>
          <table>
            <tbody>
              <tr>
                <th rowspan="1" colspan="1">
                  <bold>Original name</bold>
                </th>
                <th rowspan="1" colspan="1">
                  <bold>Current name</bold>
                </th>
                <th rowspan="1" colspan="1">
                  <bold>Proposed taxonomic arrangement</bold>
                </th>
              </tr>
              <tr>
                <td rowspan="1" colspan="3">
                  <bold><italic>“<tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadoboa"/><tp:taxon-name-part taxon-name-part-type="species" reg="aulica">aulica</tp:taxon-name-part></tp:taxon-name>”</italic> group &amp; <italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadoboa">D.</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="species" reg="kageleri">kageleri</tp:taxon-name-part></tp:taxon-name></italic></bold>
                </td>
              </tr>
              <tr>
                <td rowspan="1" colspan="1"><italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Chamaetortus">Chamaetortus</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="species" reg="aulicus">aulicus</tp:taxon-name-part></tp:taxon-name></italic> Günther, 1864</td>
                <td rowspan="1" colspan="1">
                  <italic>
                    <tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadoboa">D.</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="species" reg="aulica">aulica</tp:taxon-name-part></tp:taxon-name>
                  </italic>
                </td>
                <td rowspan="1" colspan="1">
                  <italic>
                    <tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadoboa">D.</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="species" reg="aulica">aulica</tp:taxon-name-part></tp:taxon-name>
                  </italic>
                </td>
              </tr>
              <tr>
                <td rowspan="1" colspan="1"><italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Chamaetortus">Chamaetortus</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="species" reg="aulicus">aulicus</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="subspecies" reg="flavidus">flavidus</tp:taxon-name-part></tp:taxon-name></italic> Broadley &amp; Stevens, 1971</td>
                <td rowspan="2" colspan="1">
                  <italic>
                    <tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadoboa">D.</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="species" reg="flavida">flavida</tp:taxon-name-part></tp:taxon-name>
                  </italic>
                </td>
                <td rowspan="2" colspan="1">
                  <italic>
                    <tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadoboa">D.</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="species" reg="flavida">flavida</tp:taxon-name-part></tp:taxon-name>
                  </italic>
                </td>
              </tr>
              <tr>
                <td rowspan="1" colspan="1"><italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadoboa">Dipsadoboa</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="species" reg="flavida">flavida</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="subspecies" reg="broadleyi">broadleyi</tp:taxon-name-part></tp:taxon-name></italic> Rasmussen, 1989</td>
              </tr>
              <tr>
                <td rowspan="1" colspan="1"><italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadoboa">Dipsadoboa</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="species" reg="hotamboeia">hotamboeia</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="subspecies" reg="kageleri">kageleri</tp:taxon-name-part></tp:taxon-name></italic> Uthmöller, 1939</td>
                <td rowspan="1" colspan="1">
                  <italic>
                    <tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadoboa">D.</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="species" reg="kageleri">kageleri</tp:taxon-name-part></tp:taxon-name>
                  </italic>
                </td>
                <td rowspan="1" colspan="1">
                  <italic>
                    <tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadoboa">D.</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="species" reg="kageleri">kageleri</tp:taxon-name-part></tp:taxon-name>
                  </italic>
                </td>
              </tr>
              <tr>
                <td rowspan="1" colspan="3">
                  <bold><italic>“<tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadoboa"/><tp:taxon-name-part taxon-name-part-type="species" reg="werneri">werneri</tp:taxon-name-part></tp:taxon-name>”</italic> group</bold>
                </td>
              </tr>
              <tr>
                <td rowspan="1" colspan="1"><italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadoboa">Dipsadoboa</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="species" reg="montisilva">montisilva</tp:taxon-name-part></tp:taxon-name></italic> Branch, Conradie &amp; Tolley, 2019</td>
                <td rowspan="1" colspan="1">
                  <italic>
                    <tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadoboa">D.</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="species" reg="montisilva">montisilva</tp:taxon-name-part></tp:taxon-name>
                  </italic>
                </td>
                <td rowspan="1" colspan="1">
                  <italic>
                    <tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadoboa">D.</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="species" reg="montisilva">montisilva</tp:taxon-name-part></tp:taxon-name>
                  </italic>
                </td>
              </tr>
              <tr>
                <td rowspan="1" colspan="1"><italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Crotaphopeltis">Crotaphopeltis</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="species" reg="shrevei">shrevei</tp:taxon-name-part></tp:taxon-name></italic> Loveridge, 1932</td>
                <td rowspan="1" colspan="1">
                  <italic>
                    <tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadoboa">D.</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="species" reg="shrevei">shrevei</tp:taxon-name-part></tp:taxon-name>
                  </italic>
                </td>
                <td rowspan="1" colspan="1">
                  <italic>
                    <tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadoboa">D.</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="species" reg="shrevei">shrevei</tp:taxon-name-part></tp:taxon-name>
                  </italic>
                </td>
              </tr>
              <tr>
                <td rowspan="1" colspan="1"><italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Leptodira">Leptodira</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="species" reg="werneri">werneri</tp:taxon-name-part></tp:taxon-name></italic> Boulenger, 1897</td>
                <td rowspan="1" colspan="1">
                  <italic>
                    <tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadoboa">D.</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="species" reg="werneri">werneri</tp:taxon-name-part></tp:taxon-name>
                  </italic>
                </td>
                <td rowspan="1" colspan="1">
                  <italic>
                    <tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadoboa">D.</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="species" reg="werneri">werneri</tp:taxon-name-part></tp:taxon-name>
                  </italic>
                </td>
              </tr>
              <tr>
                <td rowspan="1" colspan="3">
                  <bold><italic>“<tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadoboa"/><tp:taxon-name-part taxon-name-part-type="species" reg="duchesnii">duchesnii</tp:taxon-name-part></tp:taxon-name>”</italic> group</bold>
                </td>
              </tr>
              <tr>
                <td rowspan="1" colspan="1"><italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadomorphus">Dipsadomorphus</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="species" reg="brevirostris">brevirostris</tp:taxon-name-part></tp:taxon-name></italic> Sternfeld, 1908</td>
                <td rowspan="1" colspan="1">
                  <italic>
                    <tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadomorphus">D.</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="species" reg="brevirostris">brevirostris</tp:taxon-name-part></tp:taxon-name>
                  </italic>
                </td>
                <td rowspan="7" colspan="1">
                  <bold>
                    <italic>
                      <tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadoboa">D.</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="species" reg="duchesnii">duchesnii</tp:taxon-name-part></tp:taxon-name>
                    </italic>
                  </bold>
                </td>
              </tr>
              <tr>
                <td rowspan="1" colspan="1"><italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Leptodira">Leptodira</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="species" reg="guineensis">guineensis</tp:taxon-name-part></tp:taxon-name></italic> Chabanaud, 1920</td>
                <td rowspan="1" colspan="1"><italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadomorphus">D.</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="species" reg="guineensis">guineensis</tp:taxon-name-part></tp:taxon-name></italic>*</td>
              </tr>
              <tr>
                <td rowspan="1" colspan="1"><italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Leptodira">Leptodira</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="species" reg="duchesnii">duchesnii</tp:taxon-name-part></tp:taxon-name></italic> Boulenger, 1901</td>
                <td rowspan="5" colspan="1">
                  <italic>
                    <tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadoboa">D.</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="species" reg="duchesnii">duchesnii</tp:taxon-name-part></tp:taxon-name>
                  </italic>
                </td>
              </tr>
              <tr>
                <td rowspan="1" colspan="1"><italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadomorphus">Dipsadomorphus</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="species" reg="viridis">viridis</tp:taxon-name-part></tp:taxon-name></italic> Sternfeld, 1908</td>
              </tr>
              <tr>
                <td rowspan="1" colspan="1"><italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Leptodira">Leptodira</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="species" reg="nigeriensis">nigeriensis</tp:taxon-name-part></tp:taxon-name></italic> Werner, 1913</td>
              </tr>
              <tr>
                <td rowspan="1" colspan="1"><italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Chamaetortus">Chamaetortus</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="species" reg="aulicus">aulicus</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="subspecies" reg="ellenbergeri">ellenbergeri</tp:taxon-name-part></tp:taxon-name></italic> Chabanaud, 1916</td>
              </tr>
              <tr>
                <td rowspan="1" colspan="1"><italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadomorphus">Dipsadomorphus</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="species" reg="myops">myops</tp:taxon-name-part></tp:taxon-name></italic> Chabanaud, 1917</td>
              </tr>
              <tr>
                <td rowspan="1" colspan="3">
                  <bold><italic>“<tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadoboa"/><tp:taxon-name-part taxon-name-part-type="species">unicolor</tp:taxon-name-part></tp:taxon-name>”</italic> group</bold>
                </td>
              </tr>
              <tr>
                <td rowspan="2" colspan="1"><italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadoboa">Dipsadoboa</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="species" reg="underwoodi">underwoodi</tp:taxon-name-part></tp:taxon-name></italic> Rasmussen, 1993</td>
                <td rowspan="2" colspan="1">
                  <italic>
                    <tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadoboa">D.</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="species" reg="underwoodi">underwoodi</tp:taxon-name-part></tp:taxon-name>
                  </italic>
                </td>
                <td rowspan="1" colspan="1">
                  <italic>
                    <tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadoboa">D.</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="species" reg="underwoodi">underwoodi</tp:taxon-name-part></tp:taxon-name>
                  </italic>
                </td>
              </tr>
              <tr>
                <td rowspan="1" colspan="1">
                  <bold>
                    <tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadoboa">D.</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="uncertainty-rank">cf.</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="species" reg="underwoodi">underwoodi</tp:taxon-name-part></tp:taxon-name>
                  </bold>
                </td>
              </tr>
              <tr>
                <td rowspan="1" colspan="1"><italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadoboa">Dipsadoboa</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="species" reg="unicolor">unicolor</tp:taxon-name-part></tp:taxon-name></italic> Günther, 1858</td>
                <td rowspan="2" colspan="1">
                  <italic>
                    <tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadomorphus">D.</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="species" reg="unicolor">u.</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="subspecies" reg="unicolor">unicolor</tp:taxon-name-part></tp:taxon-name>
                  </italic>
                </td>
                <td rowspan="2" colspan="1">
                  <italic>
                    <tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadoboa">D.</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="species" reg="unicolor">unicolor</tp:taxon-name-part></tp:taxon-name>
                  </italic>
                </td>
              </tr>
              <tr>
                <td rowspan="1" colspan="1"><italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Heterurus">Heterurus</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="species" reg="bicolor">bicolor</tp:taxon-name-part></tp:taxon-name></italic> Jan, 1871 <italic>nomen dubium</italic>†</td>
              </tr>
              <tr>
                <td rowspan="1" colspan="1"><italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadoboa">Dipsadoboa</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="species" reg="unicolor">unicolor</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="subspecies" reg="viridiventris">viridiventris</tp:taxon-name-part></tp:taxon-name></italic> Laurent, 1956</td>
                <td rowspan="1" colspan="1">
                  <italic>
                    <tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadoboa">D.</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="species" reg="unicolor">u.</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="subspecies" reg="viridiventris">viridiventris</tp:taxon-name-part></tp:taxon-name>
                  </italic>
                </td>
                <td rowspan="1" colspan="1"><bold><italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadoboa">D.</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="species" reg="viridiventris">viridiventris</tp:taxon-name-part></tp:taxon-name></italic> stat. nov</bold>.</td>
              </tr>
              <tr>
                <td rowspan="1" colspan="1"><italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadoboa">Dipsadoboa</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="species" reg="riparia">riparia</tp:taxon-name-part></tp:taxon-name></italic> Trape, Mediannikov &amp; Baldé, 2023</td>
                <td rowspan="1" colspan="1">
                  <italic>
                    <tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadoboa">D.</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="species" reg="riparia">riparia</tp:taxon-name-part></tp:taxon-name>
                  </italic>
                </td>
                <td rowspan="1" colspan="1">
                  <italic>
                    <tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadoboa">D.</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="species" reg="riparia">riparia</tp:taxon-name-part></tp:taxon-name>
                  </italic>
                </td>
              </tr>
              <tr>
                <td rowspan="1" colspan="1"><italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Anoplodipsas">Anoplodipsas</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="species" reg="viridis">viridis</tp:taxon-name-part></tp:taxon-name></italic> Peters, 1869</td>
                <td rowspan="3" colspan="1"><italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadoboa">D.</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="species" reg="viridis">v.</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="subspecies" reg="viridis">viridis</tp:taxon-name-part></tp:taxon-name></italic>*</td>
                <td rowspan="3" colspan="1">
                  <bold>
                    <italic>
                      <tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadoboa">Dipsadoboa</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="species" reg="viridis">v.</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="subspecies" reg="viridis">viridis</tp:taxon-name-part></tp:taxon-name>
                    </italic>
                  </bold>
                </td>
              </tr>
              <tr>
                <td rowspan="1" colspan="1"><italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadoboa">Dipsadoboa</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="species" reg="assimilis">assimilis</tp:taxon-name-part></tp:taxon-name></italic> Matschie, 1893</td>
              </tr>
              <tr>
                <td rowspan="1" colspan="1"><italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Crotaphopeltis">Crotaphopeltis</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="species" reg="elongata">elongata</tp:taxon-name-part></tp:taxon-name></italic> Barbour, 1914</td>
              </tr>
              <tr>
                <td rowspan="1" colspan="1"><italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadoboa">Dipsadoboa</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="species" reg="elongata">elongata</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="subspecies" reg="gracilis">gracilis</tp:taxon-name-part></tp:taxon-name></italic> Laurent, 1956</td>
                <td rowspan="1" colspan="1"><italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadoboa">D.</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="species" reg="viridis">v.</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="subspecies" reg="gracilis">gracilis</tp:taxon-name-part></tp:taxon-name></italic>*</td>
                <td rowspan="1" colspan="1">
                  <bold>
                    <italic>
                      <tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadoboa">Dipsadoboa</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="species" reg="viridis">v.</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="subspecies" reg="gracilis">gracilis</tp:taxon-name-part></tp:taxon-name>
                    </italic>
                  </bold>
                </td>
              </tr>
              <tr>
                <td rowspan="1" colspan="1"><italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadophidium">Dipsadophidium</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="species" reg="weileri">weileri</tp:taxon-name-part></tp:taxon-name></italic> Lindholm, 1905</td>
                <td rowspan="2" colspan="1">
                  <italic>
                    <tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadophidium">D.</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="species" reg="weileri">weileri</tp:taxon-name-part></tp:taxon-name>
                  </italic>
                </td>
                <td rowspan="2" colspan="1">
                  <italic>
                    <tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadophidium">D.</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="species" reg="weileri">weileri</tp:taxon-name-part></tp:taxon-name>
                  </italic>
                </td>
              </tr>
              <tr>
                <td rowspan="1" colspan="1"><italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadoboa">Dipsadoboa</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="species" reg="isolepis">isolepis</tp:taxon-name-part></tp:taxon-name></italic> Boulenger, 1907</td>
              </tr>
              <tr>
                <td rowspan="1" colspan="1">NA</td>
                <td rowspan="1" colspan="1"><italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadoboa">D.</tp:taxon-name-part></tp:taxon-name></italic> (aff.) <italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadoboa"/><tp:taxon-name-part taxon-name-part-type="species" reg="weileri">weileri</tp:taxon-name-part></tp:taxon-name></italic><italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadoboa">D.</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="species" reg="unicolor">unicolor</tp:taxon-name-part></tp:taxon-name></italic> (Chippaux &amp; Jackson, 2019, partim)</td>
                <td rowspan="1" colspan="1"><bold><italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadoboa">Dipsadoboa</tp:taxon-name-part></tp:taxon-name></italic> sp</bold>.</td>
              </tr>
            </tbody>
          </table>
          <table-wrap-foot>
            <fn>
              <p>†<xref ref-type="bibr" rid="B60">Rasmussen (1993)</xref>.</p>
            </fn>
          </table-wrap-foot>
        </table-wrap>
        <sec sec-type="The ‘aulica’ group &amp; D. kageleri" id="sec14">
          <title>The ‘<tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadoboa"/><tp:taxon-name-part taxon-name-part-type="species" reg="aulica">aulica</tp:taxon-name-part></tp:taxon-name>’ group &amp; <italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadoboa">D.</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="species" reg="kageleri">kageleri</tp:taxon-name-part></tp:taxon-name></italic></title>
          <p>The phylogenetic analyses recovered <italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadoboa">D.</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="species" reg="aulica">aulica</tp:taxon-name-part></tp:taxon-name></italic>, <italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadoboa">D.</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="species" reg="flavida">flavida</tp:taxon-name-part></tp:taxon-name></italic>, and <italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadoboa">D.</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="species" reg="kageleri">kageleri</tp:taxon-name-part></tp:taxon-name></italic> as a weakly supported clade sister to the remaining members of the genus, consistent with the topology reported by <xref ref-type="bibr" rid="B11">Conradie et al. (2026)</xref>. However, both studies recovered low nodal support for the phylogenetic placement of <italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadoboa">D.</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="species" reg="kageleri">kageleri</tp:taxon-name-part></tp:taxon-name></italic>, which is therefore best treated as an ‘independent,’ ancient evolutionary lineage within the genus. <italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadoboa">Dipsadoboa</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="species" reg="aulica">aulica</tp:taxon-name-part></tp:taxon-name></italic> and <italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadoboa">D.</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="species" reg="flavida">flavida</tp:taxon-name-part></tp:taxon-name></italic> are characterized by a marbled dorsal coloration (<xref ref-type="bibr" rid="B58">Rasmussen 1989a</xref>), while <italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadoboa">D.</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="species" reg="kageleri">kageleri</tp:taxon-name-part></tp:taxon-name></italic> exhibits a uniform dark brown to gray dorsal pattern resembling that of <italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadoboa">D.</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="species" reg="shrevei">shrevei</tp:taxon-name-part></tp:taxon-name></italic>, lacks an orbital fenestra, and has a shorter snout (<xref ref-type="bibr" rid="B60">Rasmussen 1993</xref>). The molecular placement of <italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadoboa">D.</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="species" reg="kageleri">kageleri</tp:taxon-name-part></tp:taxon-name></italic> outside the ‘<italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadoboa"/><tp:taxon-name-part taxon-name-part-type="species" reg="werneri">werneri</tp:taxon-name-part></tp:taxon-name></italic>’ group indicates incongruence between the available morphological classification and the phylogenetic hypothesis recovered here. Nevertheless, because few specimens are known and no new morphological or ecological data are presented in this study, the morphological significance of this result cannot yet be resolved. The type locality of <italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadoboa">D.</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="species" reg="kageleri">kageleri</tp:taxon-name-part></tp:taxon-name></italic> at Sanya lies at approximately 1,270 m a.s.l. near the lower margin of the Kilimanjaro forest zone, and the limited available records from the Kilimanjaro–Arusha region do not demonstrate that the species is restricted to high-elevation forest. Its habitat preferences, distributional limits, and morphological affinities therefore require further investigation. For the present, <italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadoboa">D.</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="species" reg="kageleri">kageleri</tp:taxon-name-part></tp:taxon-name></italic> is treated as a distinct evolutionary lineage whose formal assignment to a species group remains unresolved.</p>
        </sec>
        <sec sec-type="The ‘werneri’ group" id="sec15">
          <title>The ‘<italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadoboa"/><tp:taxon-name-part taxon-name-part-type="species" reg="werneri">werneri</tp:taxon-name-part></tp:taxon-name></italic>’ group</title>
          <p>The phylogenetic reconstructions recovered the ‘<italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadoboa"/><tp:taxon-name-part taxon-name-part-type="species" reg="werneri">werneri</tp:taxon-name-part></tp:taxon-name></italic>’ group as monophyletic, including <italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadoboa">D.</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="species" reg="shrevei">shrevei</tp:taxon-name-part></tp:taxon-name></italic>, <italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadoboa">D.</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="species" reg="montisilva">montisilva</tp:taxon-name-part></tp:taxon-name></italic>, and <italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadoboa">D.</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="species" reg="werneri">werneri</tp:taxon-name-part></tp:taxon-name></italic>, as previously suggested (<xref ref-type="bibr" rid="B59">Rasmussen 1989b</xref>; <xref ref-type="bibr" rid="B8">Branch et al. 2019</xref>), but excluding <italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadoboa">D.</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="species" reg="kageleri">kageleri</tp:taxon-name-part></tp:taxon-name></italic>. Among them, <italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadoboa">D.</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="species" reg="montisilva">montisilva</tp:taxon-name-part></tp:taxon-name></italic> and <italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadoboa">D.</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="species" reg="werneri">werneri</tp:taxon-name-part></tp:taxon-name></italic> are confined to the Eastern Afromontane forest, whereas <italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadoboa">D.</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="species" reg="shrevei">shrevei</tp:taxon-name-part></tp:taxon-name></italic> is a common species in the savanna woodlands of Angola, Zambia, Zimbabwe, and southern DRC. Interestingly, relatively divergent mitochondrial lineages were recovered in the three nominal species, which may suggest cryptic diversification within the group, as they correspond to geographically isolated populations. Although <italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadoboa">D.</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="species" reg="shrevei">shrevei</tp:taxon-name-part></tp:taxon-name></italic> is relatively widespread across the mixed woodland savannas of southern Africa (<xref ref-type="bibr" rid="B60">Rasmussen 1993</xref>), <italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadoboa">D.</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="species" reg="werneri">werneri</tp:taxon-name-part></tp:taxon-name></italic> and <italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadoboa">D.</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="species" reg="montisilva">montisilva</tp:taxon-name-part></tp:taxon-name></italic> are known only from isolated inselbergs in Tanzania and Mozambique (<xref ref-type="bibr" rid="B8">Branch et al. 2019</xref>). Both of these areas are recognized for harboring several endemic or microendemic reptile species (e.g., <xref ref-type="bibr" rid="B7">Branch et al. 2014</xref>; <xref ref-type="bibr" rid="B10">Conradie et al. 2016</xref>; <xref ref-type="bibr" rid="B44">Menegon et al. 2022</xref>; <xref ref-type="bibr" rid="B34">Lobón-Rovira et al. 2024</xref>), highlighting the need for further investigation into the taxonomic status of these isolated populations.</p>
        </sec>
        <sec sec-type="The ‘duchesnii’ group" id="sec16">
          <title>The ‘<italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadoboa"/><tp:taxon-name-part taxon-name-part-type="species" reg="duchesnii">duchesnii</tp:taxon-name-part></tp:taxon-name></italic>’ group</title>
          <p>The results recovered the ‘<italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadoboa"/><tp:taxon-name-part taxon-name-part-type="species" reg="duchesnii">duchesnii</tp:taxon-name-part></tp:taxon-name></italic>’ group as the sister clade to the ‘<tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadoboa"/><tp:taxon-name-part taxon-name-part-type="species">unicolor</tp:taxon-name-part></tp:taxon-name>’ group, in line with the morphology-based cladogram by <xref ref-type="bibr" rid="B60">Rasmussen (1993)</xref>, including four mitochondrial lineages with low genetic divergence among them. Furthermore, all species delimitation models used in this study recovered these lineages as conspecific. This situation is further complicated because the morphology, taxonomy, and nomenclature of this group are poorly resolved. First, <italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadomorphus">D.</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="species" reg="brevirostris">brevirostris</tp:taxon-name-part></tp:taxon-name></italic> was described based on three syntypes (<xref ref-type="bibr" rid="B67">Sternfeld 1908</xref>), of which two were later considered conspecific with <italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadoboa">D.</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="species" reg="duchesnii">duchesnii</tp:taxon-name-part></tp:taxon-name></italic>, while one was considered a relevant type (mistakenly marked as the “holotype” instead of the lectotype) of <italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadomorphus">D.</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="species" reg="brevirostris">brevirostris</tp:taxon-name-part></tp:taxon-name></italic>; thus, the latter was considered valid (<xref ref-type="bibr" rid="B59">Rasmussen 1989b</xref>). However, <xref ref-type="bibr" rid="B70">Trape and Baldé (2014)</xref> disagreed with <xref ref-type="bibr" rid="B59">Rasmussen (1989b)</xref> and considered all syntypes of <italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadomorphus">D.</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="species" reg="brevirostris">brevirostris</tp:taxon-name-part></tp:taxon-name></italic> conspecific with <italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadoboa">D.</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="species" reg="duchesnii">duchesnii</tp:taxon-name-part></tp:taxon-name></italic>, placed <italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadomorphus">D.</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="species" reg="brevirostris">brevirostris</tp:taxon-name-part></tp:taxon-name></italic> into the synonymy of the latter, and resurrected <italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadomorphus">D.</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="species" reg="guineensis">guineensis</tp:taxon-name-part></tp:taxon-name></italic> for the West African short-snouted <italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadoboa">Dipsadoboa</tp:taxon-name-part></tp:taxon-name></italic> from Guinea to the Niger Delta. However, all of these taxonomic and nomenclatural acts were based solely on morphological data, and the species were not evaluated in an integrative taxonomic framework (<xref ref-type="bibr" rid="B47">Padial et al. 2010</xref>) that includes phylogenetics (<xref ref-type="bibr" rid="B74">Vences et al. 2024</xref>). A single individual from southeastern Nigeria, identified morphologically as “<italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadomorphus">D.</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="species" reg="brevirostris">brevirostris</tp:taxon-name-part></tp:taxon-name></italic>,” was found to be the sister taxon to the Upper Guinean samples of “<italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadomorphus">D.</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="species" reg="guineensis">guineensis</tp:taxon-name-part></tp:taxon-name></italic>” (Fig. <xref ref-type="fig" rid="F1">1</xref>). A similar case occurred with another equally divergent lineage from Gabon that was closely related to <italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadoboa">D.</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="species" reg="duchesnii">duchesnii</tp:taxon-name-part></tp:taxon-name></italic> from the central Congo Basin (Fig. <xref ref-type="fig" rid="F1">1</xref>).</p>
        </sec>
        <sec sec-type="The ‘unicolor’ group" id="sec17">
          <title>The ‘<tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadoboa"/><tp:taxon-name-part taxon-name-part-type="species">unicolor</tp:taxon-name-part></tp:taxon-name>’ group</title>
          <p>The ‘<tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadoboa"/><tp:taxon-name-part taxon-name-part-type="species">unicolor</tp:taxon-name-part></tp:taxon-name>’ group represents the most diverse and phylogenetically complex clade within the genus <italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadoboa">Dipsadoboa</tp:taxon-name-part></tp:taxon-name></italic>, comprising seven nominal taxa and additional candidate species. Within this group, <italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadoboa">D.</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="species" reg="underwoodi">underwoodi</tp:taxon-name-part></tp:taxon-name></italic> was recovered as the most divergent member, in agreement with <xref ref-type="bibr" rid="B60">Rasmussen (1993)</xref>. Within <italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadoboa">D.</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="species" reg="underwoodi">underwoodi</tp:taxon-name-part></tp:taxon-name></italic>, two highly divergent mitochondrial lineages were identified, corresponding to allopatric populations from the Upper Guinean and Lower Guinean (Cameroon, Gabon) forests, which appear to have diverged ~6 Mya. To date, no records have been reported from intermediate areas, suggesting either that the two populations are geographically isolated or that the area of southern Nigeria has been undersampled, but no known morphological characters distinguish them (<xref ref-type="bibr" rid="B60">Rasmussen 1993</xref>). The ‘<tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadoboa"/><tp:taxon-name-part taxon-name-part-type="species">unicolor</tp:taxon-name-part></tp:taxon-name>’ group consists of species with few morphological characters that distinguish each species (<xref ref-type="bibr" rid="B60">Rasmussen 1993</xref>) and may be indicative of cryptic speciation patterns. Further investigation of the ecological, genetic, and morphological variation in this group would help better identify speciation patterns and processes within the group.</p>
          <p>A complex pattern is observed in the <italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadoboa">D.</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="species" reg="unicolor">unicolor</tp:taxon-name-part></tp:taxon-name></italic> group and more precisely within the <italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadophidium">D.</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="species" reg="weileri">weileri</tp:taxon-name-part></tp:taxon-name></italic> complex, which includes three apparent populations in Upper Guinea (<italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadoboa">D.</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="species" reg="riparia">riparia</tp:taxon-name-part></tp:taxon-name></italic>), the Cameroon Volcanic Line (<italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadoboa">Dipsadoboa</tp:taxon-name-part></tp:taxon-name></italic> sp. “CM” and “NG”), and the Albertine Rift (<italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadoboa">D.</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="species" reg="unicolor">u.</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="subspecies" reg="viridiventris">viridiventris</tp:taxon-name-part></tp:taxon-name></italic>) (<xref ref-type="bibr" rid="B60">Rasmussen 1993</xref>; <xref ref-type="bibr" rid="B71">Trape et al. 2023</xref>). In the review of the ‘<tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadoboa"/><tp:taxon-name-part taxon-name-part-type="species">unicolor</tp:taxon-name-part></tp:taxon-name>’ species group and the genus, <italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadoboa">D.</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="species" reg="unicolor">unicolor</tp:taxon-name-part></tp:taxon-name></italic> was suggested to be a monotypic species without subspecies (<xref ref-type="bibr" rid="B60">Rasmussen 1993</xref>). However, <xref ref-type="bibr" rid="B71">Trape et al. (2023)</xref> later revalidated <italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadoboa">D.</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="species" reg="unicolor">u.</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="subspecies" reg="viridiventris">viridiventris</tp:taxon-name-part></tp:taxon-name></italic> from the Albertine Rift without providing details and stated only that <italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadoboa">D.</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="species" reg="unicolor">u.</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="subspecies" reg="viridiventris">viridiventris</tp:taxon-name-part></tp:taxon-name></italic> might represent a distinct species. The phylogenetic analyses recovered (sub)montane <italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadoboa">D.</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="species" reg="unicolor">u.</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="subspecies" reg="viridiventris">viridiventris</tp:taxon-name-part></tp:taxon-name></italic>, together with (sub)montane West African <italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadoboa">D.</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="species" reg="riparia">riparia</tp:taxon-name-part></tp:taxon-name></italic>, as a sister lineage to lowland <italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadophidium">D.</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="species" reg="weileri">weileri</tp:taxon-name-part></tp:taxon-name></italic>, while West African <italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadomorphus">D.</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="species" reg="unicolor">u.</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="subspecies" reg="unicolor">unicolor</tp:taxon-name-part></tp:taxon-name></italic> seems to be more closely related to <italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadomorphus">D.</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="species" reg="viridis">viridis</tp:taxon-name-part></tp:taxon-name></italic>. Interestingly, <xref ref-type="bibr" rid="B29">Laurent (1956)</xref> proposed that the two subspecies might co-occur in eastern Central Africa but segregate along an altitudinal gradient, with <italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadomorphus">D.</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="species" reg="unicolor">u.</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="subspecies" reg="unicolor">unicolor</tp:taxon-name-part></tp:taxon-name></italic> at lower elevations and <italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadoboa">D.</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="species" reg="unicolor">u.</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="subspecies" reg="viridiventris">viridiventris</tp:taxon-name-part></tp:taxon-name></italic> at higher elevations. However, material from lower elevations (in DRC) represented misidentified <italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadophidium">D.</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="species" reg="weileri">weileri</tp:taxon-name-part></tp:taxon-name></italic> (instead of <italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadomorphus">D.</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="species" reg="unicolor">u.</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="subspecies" reg="unicolor">unicolor</tp:taxon-name-part></tp:taxon-name></italic>), and material from mid- to higher elevations (in Uganda, Rwanda, and Burundi) represented <italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadoboa">D.</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="species" reg="unicolor">u.</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="subspecies" reg="viridiventris">viridiventris</tp:taxon-name-part></tp:taxon-name></italic>, with shallow genetic divergence between populations and some phylogeographic structure. Nevertheless, this pattern does not support clear elevational segregation of these eastern populations and suggests that all represent a single taxon, probably a separate species, <italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadoboa">D.</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="species" reg="viridiventris">viridiventris</tp:taxon-name-part></tp:taxon-name></italic> (new status).</p>
          <p>Finally, a high degree of phylogenetic structure was recovered within <italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadomorphus">D.</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="species" reg="viridis">viridis</tp:taxon-name-part></tp:taxon-name></italic>. Among these samples, a lineage was identified that can be readily assigned to <italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadoboa">D.</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="species" reg="viridis">v.</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="subspecies" reg="gracilis">gracilis</tp:taxon-name-part></tp:taxon-name></italic> from the northeastern and central Congo Basin. In addition, four other equally divergent mitochondrial lineages were recovered that are distributed along the Upper and Lower Guinean forests. However, none of these lineages can be confidently assigned to the nominotypical <italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadomorphus">D.</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="species" reg="viridis">viridis</tp:taxon-name-part></tp:taxon-name></italic> because of the problematic nature of the type locality, which is erroneously listed as ‘New Caledonia’ (<xref ref-type="bibr" rid="B60">Rasmussen 1993</xref>). Assignment of the type specimen could possibly be resolved using museomics, whereby ancient DNA is extracted and sequenced, allowing identification against existing DNA databases (<xref ref-type="bibr" rid="B30">Lalueza-Fox 2022</xref>). Indeed, this approach could also assist in confirming the validity of other taxa with dubious taxonomic assignments within this species group, such as <italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Heterurus">Heterurus</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="species" reg="bicolor">bicolor</tp:taxon-name-part></tp:taxon-name></italic> Jan, 1871, <italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Crotaphopeltis">Crotaphopeltis</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="species" reg="elongata">elongata</tp:taxon-name-part></tp:taxon-name></italic> Barbour, 1914, or <italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadoboa">Dipsadoboa</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="species" reg="assimilis">assimilis</tp:taxon-name-part></tp:taxon-name></italic> Matschie, 1893.</p>
        </sec>
      </sec>
      <sec sec-type="Biogeography, origin, and evolution" id="sec18">
        <title>Biogeography, origin, and evolution</title>
        <p>The results support <xref ref-type="bibr" rid="B60">Rasmussen’s (1993)</xref> suggestion that the Lower Guinean forests (Area II in <xref ref-type="bibr" rid="B60">Rasmussen 1993</xref>) within the Congo Basin are the main diversity hotspot for <italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadoboa">Dipsadoboa</tp:taxon-name-part></tp:taxon-name></italic>, while also highlighting the Eastern Afromontane region (Area VII in <xref ref-type="bibr" rid="B60">Rasmussen 1993</xref>) as an important region for its diversification. The ancestral range reconstruction indicates the Eastern Afromontane region as the most probable region of origin of the genus (Fig. <xref ref-type="fig" rid="F6">6B</xref>), thus suggesting a forest-dwelling origin of the group. This conclusion is reinforced by the sister genus <italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Crotaphopeltis">Crotaphopeltis</tp:taxon-name-part></tp:taxon-name></italic>, for which East and Southern Africa have been proposed as the regions of origin (<xref ref-type="bibr" rid="B18">Engelbrecht et al. 2020</xref>). Other studies have suggested ancestral origins of African forest clades in the Eastern Afromontane region (<xref ref-type="bibr" rid="B22">Fjeldså and Lovett 1997</xref>; <xref ref-type="bibr" rid="B21">Fjeldså and Bowie 2008</xref>). The <abbrev xlink:title="Dispersal–Extinction–Cladogenesis model">DEC</abbrev>+J model emerged as the best-fitting scenario, revealing low dispersal (<italic>d</italic> = 0.002), negligible extinction, and a significant role of founder-event speciation (<italic>j</italic> = 0.18), suggesting that rare long-distance dispersal followed by lineage isolation (vicariance) shaped the current distribution of <italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadoboa">Dipsadoboa</tp:taxon-name-part></tp:taxon-name></italic> across African forests and savanna woodlands (<xref ref-type="bibr" rid="B61">Ree and Smith 2008</xref>).</p>
        <p>Diversification of <italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadoboa">Dipsadoboa</tp:taxon-name-part></tp:taxon-name></italic> seemed to occur independently between the Eastern Afromontane forests and southern savannas and within Central Africa (Fig. <xref ref-type="fig" rid="F6">6</xref>). Furthermore, the model recovered two independent divergence events occurring between Eastern Afromontane pockets and southern savannas in the early and mid-Miocene. This pattern is consistent with the tectonic evolution of the East African Rift, which began developing during the mid–late Miocene, with further rift propagation continuing into the Plio–Pleistocene (<xref ref-type="bibr" rid="B40">McConnell 1972</xref>; <xref ref-type="bibr" rid="B37">Macgregor 2015</xref>; <xref ref-type="bibr" rid="B41">Michon et al. 2022</xref>). It is also consistent with Miocene climatic fluctuations and the associated shifts in the distribution of forest and savanna habitats across Africa, which likely promoted lineage isolation and diversification, particularly through the persistence of climatic refugia on East African inselbergs (e.g., <xref ref-type="bibr" rid="B33">Loader et al. 2014</xref>; <xref ref-type="bibr" rid="B13">Couvreur et al. 2021</xref>).</p>
        <p>Climatic fluctuations seem to have also played an important role in shaping diversification within the Congo Basin, where at least four diversification events are inferred to have occurred during the mid- and late Miocene (18–5 Mya). These results are consistent with studies of other forest-dwelling vertebrate groups (<xref ref-type="bibr" rid="B50">Portillo et al. 2015</xref>, <xref ref-type="bibr" rid="B51">2018</xref>; <xref ref-type="bibr" rid="B45">Nicolas et al. 2020</xref>; <xref ref-type="bibr" rid="B46">Onditi et al. 2021</xref>; <xref ref-type="bibr" rid="B34">Lobón-Rovira et al. 2024</xref>), suggesting that climatic refugia and savanna expansion drove multiple vicariant events across the Congo Basin, with subsequent secondary contacts during forest expansions.</p>
        <p>The ancestral range reconstruction for the Upper Guinea region suggests three independent colonization events followed by isolation from Central African lineages. However, a broader ancestral distribution across West and Central Africa cannot be excluded, with subsequent isolation driven by climatic refugia in the region, which is well known for its pronounced climatic fluctuations (<xref ref-type="bibr" rid="B19">Ernst et al. 2025</xref>).</p>
        <p>Overall, although the ancestral range reconstruction supports founder-event speciation (dispersal followed by isolation) as the most plausible scenario, the strong geographic structuring observed in several lineages indicates that vicariant processes were also important, particularly because of climatic refugia in the Congo Basin and the origin and expansion of the Rift Valley between East and Southern Africa. Together, these results suggest that both dispersal events and historical isolation have shaped the diversification and geographic patterns of <italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadoboa">Dipsadoboa</tp:taxon-name-part></tp:taxon-name></italic> in Africa. However, the biogeographic results should be interpreted with the caveat that the phylogenetic reconstructions are based on mitochondrial DNA data; therefore, the topologies and time estimates would greatly benefit from the inclusion of nuclear markers in future studies for more robust interpretations.</p>
      </sec>
    </sec>
    <sec sec-type="Conclusion" id="sec19">
      <title>Conclusion</title>
      <p>In summary, this study provides the most comprehensive phylogenetic and biogeographic hypothesis of <italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadoboa">Dipsadoboa</tp:taxon-name-part></tp:taxon-name></italic> systematics to date. The genus is monophyletic and sister to <italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Crotaphopeltis">Crotaphopeltis</tp:taxon-name-part></tp:taxon-name></italic>. Both species delimitation and phylogenetic analyses recover well-supported clades corresponding largely to morphological groups, but some taxa show unresolved placements or evidence of cryptic diversity (Table <xref ref-type="table" rid="T2">2</xref>). This could be a consequence of poor resolution resulting from limited sampling of some taxa (specifically, <italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadoboa">D.</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="species" reg="kageleri">kageleri</tp:taxon-name-part></tp:taxon-name></italic> and <italic><tp:taxon-name><tp:taxon-name-part taxon-name-part-type="genus" reg="Dipsadoboa">D.</tp:taxon-name-part> <tp:taxon-name-part taxon-name-part-type="species" reg="riparia">riparia</tp:taxon-name-part></tp:taxon-name></italic>), which hinders robust comparisons. Furthermore, as the dataset is restricted to mitochondrial markers, a comprehensive and integrative examination of this mitochondrial-based hypothesis is recommended, using morphological and nuclear data to clarify its evolutionary significance and the taxonomic status of some (candidate) taxa.</p>
      <p>Finally, the results highlight the western Central African forests as the main diversity hotspot, while Eastern Afromontane forests seem to have played a pivotal role in the genus’s origin and early diversification. Biogeographic reconstructions suggest that both long-distance dispersal events and historical vicariance, driven by climatic fluctuations and the formation of African biogeographic barriers such as the Great Rift Valley, contributed to the current distribution and diversification of the genus. Altogether, this work establishes a robust framework for future integrative studies and provides essential baseline data for understanding the evolutionary history and conservation of African forest and wooded savanna snakes.</p>
    </sec>
  </body>
  <back>
    <ack>
      <title>Acknowledgements</title>
      <p>The authors thank Aaron M. Bauer (VU), Werner Conradie (PEM), and Garin Cael (RMCA) for providing valuable historical archival material for this study. The authors are also grateful to Aurélien Miralles (MNHN), Frank Tillack (ZMB), and Frank Glaw (ZSM) for providing detailed photographs of the type specimens. The authors thank David Buckley (UAM) for his constant advice and support to JLR in the analysis of complex genomic data. EG, CK, FMM, and GB are grateful to the Centre de Recherche en Sciences Naturelles for project support and permits and to the Institut Congolais pour la Conservation de la Nature for permits in protected areas. The authors thank the villages of Baposso, Mambonga, and Moukoumbi, Ngounie Province, Gabon, and the field team for their efforts during the 2024 Gabon expedition: Pierre Masala, Bloy Ngoulou, Hermine Ina, Emily Forner, Joseph Madden, and Sverre Finney. The authors thank Kelly Zamudio and David Cannatella for their support, laboratory space, and laboratory materials. The staff of IRAF (Institut de Recherches Agronomiques et Forestières) and CENAREST (Centre National de la Recherche Scientifique et Technologique) are also thanked. All work in Gabon was conducted according to national laws and permits (CENAREST: N°AROOI/24/MERSIT/CENAREST/CG/CST/CSAR; ANPN: N°AE24008 PR/ANPN/SE/CS/MMCL). Authorizations to sample and export voucher specimens and tissues from Cameroon were granted by the Ministère des Forêts et de la Faune (MINFOF, Ministry of Forestry and Wildlife) and Ministère de la Recherche Scientifique et de l’Innovation (MINRESI, Ministry of Scientific Research and Innovation); permit N° 00000030/MINRESI/B00/C00/C10/C12 of 8 March 2019. The samples contributed by VG were obtained through many years of fieldwork across several Central African countries, particularly in the Democratic Republic of the Congo. This would not have been possible without the additional samples, fieldwork, or logistical support provided by the following individuals, who are sincerely thanked (alphabetically): J.B. Akuboy, J. Czurda, M. Dolinay, E.B. Fokam, F. Kihambu Fundji, O. Kopecký, and G.C. Tasse Taboue. Various authorities issued permits for research, collection, or export, including the Ministère de l’Environnement, Développement Durable et Nouvelle Économie du Climat, Kinshasa; Institut Congolais pour la Conservation de la Nature, Kinshasa; Centre de Surveillance de la Biodiversité, Kisangani; Ministère de la Recherche Scientifique et de l’Innovation Technologique, Brazzaville; Ministère de l’Economie Forestière, du Développement Durable et de l’Environnement, Brazzaville; and Institut National de Recherche en Sciences Exactes et Naturelles, Brazzaville. The authors particularly thank V. Kakengi and J. Keyyu (TAWIRI), as well as W. Ngalason, F. Magige, F. Stephano, and the late K. Howell (University of Dar es Salaam), for their kind assistance and support in Tanzania. Natural History Museum Science Investment Funds and RE (Hazina Project GG-0000001649) provided financial support. The authors are grateful to the three reviewers and the editors for their insightful comments and suggestions, which substantially strengthened this study.</p>
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    <sec sec-type="Additional information" id="sec20">
      <title>Additional information</title>
      <sec sec-type="Conflict of interest" id="sec21">
        <title>Conflict of interest</title>
        <p>The authors have declared that no competing interests exist.</p>
      </sec>
      <sec sec-type="Ethical statement" id="sec22">
        <title>Ethical statement</title>
        <p>No ethical statement was reported.</p>
      </sec>
      <sec sec-type="Artificial Intelligence (AI) use" id="sec23">
        <title>Artificial Intelligence (AI) use</title>
        <p>The authors accept full responsibility for the content of the manuscript, including the disclosure of any use of AI. AI was not used in the production of this manuscript, other than for assistance in disentangling coding errors.</p>
      </sec>
      <sec sec-type="Funding" id="sec24">
        <title>Funding</title>
        <p>JLR is supported by a Juan de la Cierva Grant from the Spanish Government under Grant JDC2024-053262-I. EWB was funded by the Stengl-Wyer Fellowship and the Biodiversity Center at the University of Texas at Austin. Fieldwork by EG in DRC and subsequent laboratory work at UTEP were funded by the Percy Sladen Memorial Fund, an IUCN/SSC Amphibian Specialist Group Seed Grant, K. Reed, M.D., research funds from the Department of Biology at Villanova University, two National Geographic Research and Exploration Grants (nos. 8556-08 and WW-R018-17), a University of Texas System Rising STARs Award, UTEP, the Conservation, Food &amp; Health Foundation, and the US National Science Foundation (DEB-1145459). EG thanks Ana Betancourt of the Border Biomedical Research Center (BBRC) Genomics Analysis Core Facility for services and facilities provided. The Museu de História Natural de Maputo is thanked for logistical assistance with permitting and permissions in Mozambique (nos. 129/DPAN/2014, 507/DPAZ/SPFFB/420/2014, 315/MNH/E27/2014, 08/2018, 282/DPTADERZ/GD/SPFFB/420, 730/DPTADER/NPL/REP, 1090/DPTADER/SPFFB/600), the National Geographic Society Committee for Research and Exploration (CRE 9281-13), the South African National Biodiversity Institute, and the National Research Foundation of South Africa (Grant no. 92776) for providing funding, and Khangela Safaris for logistical support for the Mozambique survey. This work was supported by Grant 5U54MD007592 from the National Institute on Minority Health and Health Disparities (NIMHD), a component of the US National Institutes of Health (NIH). Research contributions by VG and TN were supported by the Czech Science Foundation (23-07331S), and VG was also supported by the Ministry of Culture of the Czech Republic (DKRVO 2024–2028/6.l.c, National Museum of the Czech Republic, 00023272).</p>
      </sec>
      <sec sec-type="Author contributions" id="sec25">
        <title>Author contributions</title>
        <p>Conceptualization: J.L.R., E.W.B., G.F.M.J.; Methodology: J.L.R., E.W.B., E.G., G.F.M.J., K.A.T., V.G. ; Data curation: J.L.R., E.W.B., B.A.D., E.G., G.F.M.J., J.P., K.A.T., M.M., M.O.R., P.S.C., S.L., T.N., V.G.; Resources: J.L.R., E.W.B., B.A.D., E.G., G.F.M.J., J.P., K.A.T., M.M., M.O.R., P.S.C., S.L., T.N., V.G.; Investigation: J.L.R., E.G., T.N.; Formal analysis: J.L.R.; Funding acquisition: J.L.R., E.W.B., E.G., G.F.M.J., K.A.T., M.O.R., V.G.; Validation: All authors; Writing – original draft: J.L.R.; Writing – review &amp; editing: All authors.</p>
      </sec>
      <sec sec-type="Author ORCIDs" id="sec26">
        <title>Author ORCIDs</title>
        <p>J. Lobón-Rovira <ext-link xlink:href="https://orcid.org/0000-0003-4380-9427" ext-link-type="uri">https://orcid.org/0000-0003-4380-9427</ext-link></p>
        <p>E.W. Basham <ext-link xlink:href="https://orcid.org/0000-0002-0167-7908" ext-link-type="uri">https://orcid.org/0000-0002-0167-7908</ext-link></p>
        <p>V. Gvoždík <ext-link xlink:href="https://orcid.org/0000-0002-4398-4076" ext-link-type="uri">https://orcid.org/0000-0002-4398-4076</ext-link></p>
        <p>E. Greenbaum <ext-link xlink:href="https://orcid.org/0000-0003-1674-1316" ext-link-type="uri">https://orcid.org/0000-0003-1674-1316</ext-link></p>
        <p>G. Badjedjea <ext-link xlink:href="https://orcid.org/0000-0003-4284-4327" ext-link-type="uri">https://orcid.org/0000-0003-4284-4327</ext-link></p>
        <p>A. Bamba-Kaya <ext-link xlink:href="https://orcid.org/0009-0007-2712-7334" ext-link-type="uri">https://orcid.org/0009-0007-2712-7334</ext-link></p>
        <p>B.A. Dobbins <ext-link xlink:href="https://orcid.org/0009-0006-8258-8646" ext-link-type="uri">https://orcid.org/0009-0006-8258-8646</ext-link></p>
        <p>S.P. Loader <ext-link xlink:href="https://orcid.org/0000-0003-4162-0575" ext-link-type="uri">https://orcid.org/0000-0003-4162-0575</ext-link></p>
        <p>J.V. Lyakurwa <ext-link xlink:href="https://orcid.org/0000-0002-8252-0880" ext-link-type="uri">https://orcid.org/0000-0002-8252-0880</ext-link></p>
        <p>T. Nečas <ext-link xlink:href="https://orcid.org/0000-0002-5060-8394" ext-link-type="uri">https://orcid.org/0000-0002-5060-8394</ext-link></p>
        <p>J. Penner <ext-link xlink:href="https://orcid.org/0000-0001-8166-5992" ext-link-type="uri">https://orcid.org/0000-0001-8166-5992</ext-link></p>
        <p>M.-O. Rödel <ext-link xlink:href="https://orcid.org/0000-0002-1666-195X" ext-link-type="uri">https://orcid.org/0000-0002-1666-195X</ext-link></p>
        <p>E. Tobi <ext-link xlink:href="https://orcid.org/0000-0002-6199-290X" ext-link-type="uri">https://orcid.org/0000-0002-6199-290X</ext-link></p>
        <p>K.A. Tolley <ext-link xlink:href="https://orcid.org/0000-0002-7778-1963" ext-link-type="uri">https://orcid.org/0000-0002-7778-1963</ext-link></p>
        <p>G.F.M. Jongsma <ext-link xlink:href="https://orcid.org/0000-0001-8790-2610" ext-link-type="uri">https://orcid.org/0000-0001-8790-2610</ext-link></p>
      </sec>
      <sec sec-type="Data availability" id="sec27">
        <title>Data availability</title>
        <p>Genetic data generated for this study are available in GenBank (<ext-link xlink:href="https://www.ncbi.nlm.nih.gov/genbank/" ext-link-type="uri">https://www.ncbi.nlm.nih.gov/genbank/</ext-link>). GenBank accession numbers are provided in Suppl. material <xref ref-type="supplementary-material" rid="S1">1</xref>: table S2.</p>
      </sec>
    </sec>
    <sec sec-type="supplementary-material">
      <title>Supplementary materials</title>
      <supplementary-material id="S1" position="float" orientation="portrait" xlink:type="simple">
        <object-id content-type="doi">10.21425/fob.19.195124.suppl1</object-id>
        <object-id content-type="arpha">7DD8220F-C7F6-598C-AA88-D1FCA487BFE3</object-id>
        <label>Supplementary materials
 Supplementary material 1</label>
        <caption>
          <p>Supplementary information (.pdf)</p>
        </caption>
        <media xlink:href="biogeography-19-001_article-195124__-s001.pdf" mimetype="application" mime-subtype="pdf" position="float" orientation="portrait" id="oo_1793697.pdf">
          <uri content-type="original_file">https://binary.pensoft.net/file/1793697</uri>
        </media>
      </supplementary-material>
    </sec>
  </back>
</article>
