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USGS · 70020349

A problematic early tetrapod from the Mississippian of Nevada

K.S. Thomson·N.S. Shubin·F. G. Poole
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Abstract

We report here the discovery of a new taxon of Paleozoic tetrapod from the Late Mississippian of Nevada (330–340 Ma). It has a unique vertebral column with principal centra having vertical anterior and posterior faces, ventrally incomplete accessory centra located antero-dorsally in each centrum, and enlarged presacral/sacral vertebrae. The head and pectoral girdle were not preserved but the large femur, robust pelvic girdle and enlarged sacral vertebrae possibly indicate a terrestrial mode of life. This new form significantly extends the western geographic range of known Mississippian tetrapods. It presents a mosaic of primitive and derived features, indicating that continued revision of traditional accounts of vertebral homology and the early diversifications of Paleozoic tetrapods will be necessary.

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BibTeXRIS

K.S. Thomson, N.S. Shubin, F. G. Poole. 1998. A problematic early tetrapod from the Mississippian of Nevada. https://doi.org/10.1080/02724634.1998.10011059

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