Thursday, February 2, 2012

[Paleontology • 2009] Armadillosuchus arrudai • An armadillo-like sphagesaurid crocodyliform from the Late Cretaceous of Brazil



Abstract
The Sphagesauridae is a family of Crocodyliformes exclusively known for the Brazilian Late Cretaceous Bauru Basin. This lineage reveals how diverse was the morphology and ecology of terrestrial Crocodyliformes during the Late Cretaceous of Gondwana. Here is described Armadillosuchus arrudai gen. et sp. nov., a sphagesaurid that presents some mammal-like morphological features, such as propalinal and alternate unilateral jaw occlusion pattern and heavy body armor, composed of a rigid shield and mobile-banded section as in extant armadillos (Xenarthra, Dasypodidae). These unusual morphological features contrast to the double row of osteoderms observed on the closest relatives of A. arrudai. As its mammal analogs, A. arrudai presents some evidence of fossoriality and an exclusive terrestrial life style in contrast to the extant alligatorids and crocodylids.

Keywords: Crocodyliformes; Sphagesauridae; Bauru Basin; Late Cretaceous; Brazil


Fig. 2. Armadillosuchus arrudai gen. et sp. nov. (UFRJ DG 303-R), skull, cervical shield and humerus in (a) dorsal view, (b) lateral left view. Armadillosuchus arrudai gen. et sp. nov. (MPMA-64-0001-04)


Life restoration of Armadillosuchus arrudai


Marinho, Thiago S.; and Carvalho, Ismar S. 2009. An armadillo-like sphagesaurid crocodyliform from the Late Cretaceous of Brazil. Journal of South American Earth Sciences 27 (1): 36–41.