Tuesday, April 2, 2013

[PalaeoIchthyology • 2013] Planohybodus marki • a new freshwater hybodontid shark from the Early Cretaceous of northeastern Brazil

Artistic reconstruction of the “Cascudo” outcrop vertebrate fauna showing Planohybodus marki sp. nov., Lepidotes-like fishes, Mawsonia and an indeterminate crocodilomorph.
Illustrator: Voltaire P. Neto | http://facebook.com/photo.php?fbid=638200322872699

A new species of hybodontid shark is described for the Lower Cretaceous of Brazil. The type specimen is derived from pre-Aptian strata of Malhada Vermelha Formation, Lima Campos Basin (Ceará State, northeastern Brazil), with referred material from the Missão Velha Formation of Araripe Basin, northeastern Brazil. The new taxon differs from other Planohybodus species by the presence of a stronger tooth ornamentation characterized by simple, usually non-branching cristae that nearly reach the apex of the main cusp as well as distinctly divergent lateral cusplets. In addition, certain North-American specimens formerly attributed to Hybodus are identified as Planohybodus. The new species presented herein, in addition to the North-American remains, represents an important contribution to the knowledge of the distribution of Planohybodus, expanding the geographic range of the genus to South and North America in the Late Jurassic and Early Cretaceous.

Keywords: Planohybodus; Hybodontidae; Malhada Vermelha Formation; Lima Campos Basin; Early Cretaceous; Missão Velha Formation

Felipe L. Pinheiro, Ana Emilia Q. de Figueiredo, , Paula C. Dentzien-Dias, Daniel C. Fortier, Cesar L. Schultz, Maria Somália S. Viana. 2013. Planohybodus marki sp. nov., a new fresh-water hybodontid shark from the Early Cretaceous of northeastern Brazil. Cretaceous Research. 41, April 2013, 210–216. http://dx.doi.org/10.1016/j.cretres.2012.12.005