The oldest Brazilian snakes from the early Late Cretaceous (Cenomanian)
Foi descrita a mais antiga e primitiva espécie de serpente no Brasil, viveu no Cenomaniano, divisão do Período Cretáceo, no Maranhão. Recebeu o nome de Seismophis septentrionalis.
ANNIE S. HSIOU, ADRIANA M. ALBINO, MANUEL A. MEDEIROS, and RONNY A.B.
Annie S. Hsiou, Adriana M. Albino, Manuel A. Medeiros, and Ronny A.B. Santos. 201X. The oldest
Brazilian snakes from the early Late Cretaceous (Cenomanian). Acta Palaeontologica Polonica XX
(X): xxx-xxx. http://dx.doi.org/10.4202/app.2012.0091
Copyright © 201X A.S. Hsiou et al. This is an open-access article distributed under the terms of the
Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
South American Mesozoic snake diversity is mostly represented by genera from the Cenomanian (Najash), Santonian-Campanian (Dinilysia), and Campanian-Maastrichtian (Alamitophis, Patagoniophis, Rionegrophis, and Australophis) of Patagonia, Argentina. In this paper, we describe a new snake genus and species, Seismophis septentrionalis, from the early Late Cretaceous (Cenomanian) of the Alcântara Formation, Maranhão, northeastern Brazil. The new snake comprises a posteriormost trunk vertebra and possibly a poorly preserved midtrunk vertebra. Both vertebrae share small size, zygosphene moderately thick with a rectilinear roof, absence of paracotylar foramina, presence of parazygantral foramina, and strongly marked parasagittal ridges of the neural arch. The new snake is here considered of uncertain systematic affinities, but probably close to the limbed snake Najash rionegrina. Although the material is very fragmentary and the systematic assignment is still unresolved, this snake represents the oldest, as well as probably the most primitive snake from Brazil.