Evolução 286: Seismophis, a serpente mais antiga do Brasil

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.

FONTE: 
 ANNIE S. HSIOU, ADRIANA M. ALBINO, MANUEL A. MEDEIROS, and RONNY A.B.
 SANTOS

 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.
RESUMO ORIGINAL:
 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.