New insights into the origins and radiation of the mid-Palaeozoic Gondwanan stem tetrapods

ABSTRACT The earliest tetrapodomorph fishes appear in Chinese deposits of Early Devonian age, and by the Middle Devonian they were widespread globally. Evidence for the earliest digitated tetrapods comes from largely uncontested Middle Devonian trackways and Late Devonian body fossils. The East Gond...

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Bibliographic Details
Published in:Earth and Environmental Science Transactions of the Royal Society of Edinburgh
Main Authors: LONG, John A., CLEMENT, Alice M., CHOO, Brian
Format: Article in Journal/Newspaper
Language:English
Published: Cambridge University Press (CUP) 2018
Subjects:
Online Access:http://dx.doi.org/10.1017/s1755691018000750
https://www.cambridge.org/core/services/aop-cambridge-core/content/view/S1755691018000750
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Summary:ABSTRACT The earliest tetrapodomorph fishes appear in Chinese deposits of Early Devonian age, and by the Middle Devonian they were widespread globally. Evidence for the earliest digitated tetrapods comes from largely uncontested Middle Devonian trackways and Late Devonian body fossils. The East Gondwana Provence (Australasia, Antarctica) fills vital gaps in the phylogenetic and biogeographic history of the tetrapods, with the Gondwanan clade Canowindididae exhibiting a high degree of endemism within the early part of the stem tetrapod radiation. New anatomical details of Koharalepis , from the Middle Devonian Aztec Siltstone of Antarctica, are elucidated from synchrotron scan data. These include the position of the orbit, the condition of the hyomandibular, the shape of the palate and arrangement of the vomerine fangs. Biogeographical and phylogenetic models of stem tetrapod origins and radiations are discussed.