AUTHOR=Coster Pauline M. C. , Beard K. Christopher , Salem Mustafa J. , Chaimanee Yaowalak , Jaeger Jean-Jacques 

TITLE=New fossils from the Paleogene of central Libya illuminate the evolutionary history of endemic African anomaluroid rodents

JOURNAL=Frontiers in Earth Science

VOLUME=3

YEAR=2015

URL=https://www.frontiersin.org/journals/earth-science/articles/10.3389/feart.2015.00056

DOI=10.3389/feart.2015.00056

ISSN=2296-6463

ABSTRACT=<p>Anomaluroid rodents show interesting biogeographic and macroevolutionary patterns, although their fossil record is meager and knowledge of the natural history of extant members of the clade remains inadequate. Living anomaluroids (Anomaluridae) are confined to equatorial parts of western and central Africa, but the oldest known fossil anomaluroid (<italic>Pondaungimys</italic>) comes from the late middle Eocene of Myanmar. The first appearance of anomaluroids in the African fossil record coincides with the first appearances of hystricognathous rodents and anthropoid primates there. Both of the latter taxa are widely acknowledged to have originated in Asia, suggesting that anomaluroids may show a concordant biogeographic pattern. Here we describe two new taxa of African Paleogene anomaluroids from sites in the Sirt Basin of central Libya. These include a new Eocene species of the nementchamyid genus <italic>Kabirmys</italic>, which ranks among the oldest African anomaluroids recovered to date, and a new genus and species of Anomaluridae from the early Oligocene, which appears to be closely related to extant <italic>Zenkerella</italic>, the only living non-volant anomalurid. Phylogenetic analyses incorporating the new Libyan fossils suggest that anomaluroids are not specially related to Zegdoumyidae, which are the only African rodents known to antedate the first appearance of anomaluroids there. The evolution of gliding locomotion in Anomaluridae appears to conflict with traditional assessments of relationships among living anomalurid taxa. If the historically accepted division of Anomaluridae into Anomalurinae (extant and Miocene <italic>Anomalurus</italic> and Miocene <italic>Paranomalurus</italic>) and Zenkerellinae (extant and Miocene <italic>Zenkerella</italic> and extant <italic>Idiurus</italic>) is correct, then either gliding locomotion evolved independently in Anomalurinae and <italic>Idiurus</italic> or non-volant <italic>Zenkerella</italic> evolved from a gliding ancestor. Anatomical data related to gliding in Anomaluridae are more consistent with a non-traditional systematic arrangement, whereby non-volant <italic>Zenkerella</italic> is the sister group of a clade including both <italic>Anomalurus</italic> and <italic>Idiurus</italic>.</p><p><italic>Kabirmys prius</italic>: <ext-link ext-link-type="uri" xlink:href="http://zoobank.org/urn:lsid:zoobank.org:act:C4FC0114-DAA6-4D12-BD3C-F5900BE1AD1E" xmlns:xlink="http://www.w3.org/1999/xlink">urn:lsid:zoobank.org:act:C4FC0114-DAA6-4D12-BD3C-F5900BE1AD1E</ext-link></p><p><italic>Prozenkerella</italic>: <ext-link ext-link-type="uri" xlink:href="http://zoobank.org/urn:lsid:zoobank.org:act:144DC508-333F-4746-A313-A0556804D7F1" xmlns:xlink="http://www.w3.org/1999/xlink">urn:lsid:zoobank.org:act:144DC508-333F-4746-A313-A0556804D7F1</ext-link></p><p><italic>Prozenkerella saharaensis</italic>: <ext-link ext-link-type="uri" xlink:href="http://zoobank.org/urn:lsid:zoobank.org:act:76992C9D-D754-40E9-B8E2-E786A5BC7E8C" xmlns:xlink="http://www.w3.org/1999/xlink">urn:lsid:zoobank.org:act:76992C9D-D754-40E9-B8E2-E786A5BC7E8C</ext-link><ext-link ext-link-type="uri" xlink:href="http://zoobank.org/urn:lsid:zoobank.org:pub:866B8A65-BCB2-4E8F-B6FA-24637606528C" xmlns:xlink="http://www.w3.org/1999/xlink">urn:lsid:zoobank.org:pub:866B8A65-BCB2-4E8F-B6FA-24637606528C</ext-link></p>