A New Abelisaurid (Tralkasaurus cuyi) from Argentina

A team of scientists based in Argentina have described a new species of abelisaurid from the Huincul Formation in northern Patagonia.  The new dinosaur is represented by a fragmentary skeleton consisting of caudal vertebrae (tail bones), a bone from the upper jaw (maxilla), a distorted pelvic girdle and sacral vertebrae.  Although the fossils were found in a disarticulated state and quite widely scattered, it is likely that the bones represent a single, individual animal.

Tralkasaurus cuyi

With an estimated body length of around five metres and a hip height of approximately 1.5 metres, this newest member of the Abelisauridae, named Tralkasaurus cuyi, is much smaller than abelisaurs such as Carnotaurus sastrei, Abelisaurus comahuensis and Ekrixinatosaurus novasi. 

Writing in the “Journal of South American Earth Sciences”, the researchers, which included Mauricio Cerroni, a PhD student at the Museo Argentino de Ciencias Naturales, Buenos Aires (Argentina), conclude that Tralkasaurus probably occupied a different ecological niche compared to the much larger and heavier Late Cretaceous abelisaurids.

A Size Comparison Between Carnotaurus sastrei and Tralkasaurus cuyi

Picture credit: Everything Dinosaur

A New “Thunder Lizard”

This new dinosaur was found at the Violante Farm site, in Río Negro province (northern Patagonia).  The sandstones of the Huincul Formation has yielded a diverse range of theropods including the giant carcharodontosaurid Mapusaurus (M. roseae), which is estimated to have measured around 12 metres in length along with the at least 6-metre-long Gualicho (G. shinyae), tentatively described as a member of the Neovenatoridae family and two other abelisaurids Skorpiovenator (S. bustingorryi) and Ilokelesia (I. aguadagrandensis).

The genus name translates as “thunder lizard”, in the native Mapuche language.

Life Reconstruction with Scale Tralkasaurus cuyi

Picture credit: Everything Dinosaur

Being much smaller than other abelisaurids such as Abelisaurus and Carnotaurus suggests that this new taxon probably occupied a different ecological niche within the ecosystem.

The scientific paper: “A new abelisaurid from the Huincul Formation (Cenomanian-Turonian; Upper Cretaceous) of Río Negro province, Argentina” by M. A. Cerroni, M. J. Motta, F. L. Agnolína, A. M. Aranciaga Rolando, F. Brissón Egli and F. E. Novas published in the Journal of South American Earth Sciences.

The Everything Dinosaur website: Everything Dinosaur.