Trucidocynodon


Trucidocynodon is an extinct, monotypic genus of cynodonts from Upper Triassic of Brazil. Trucidocynodon riograndensis is the only species described for this genus.
Trucidocynodon riograndensis, the sole species in Trucidocynodon, lived in what is now southern Brazil 220 million years ago. Fossils of Trucidocynodon were discovered in Santa Maria Formation outcrops in Paleorrota geopark Agudo. T. riograndensis is similar to the Ecteninion lunensis from the Upper Triassic Ischigualasto formation in Argentina.

Size

Trucidocynodon is particularly notable for its large size: based on its skull and forelimb proportions, it is thought to be comparable in size to a modern leopard. This contradicts the idea that cynodonts became less ecologically diverse due to competition from archosaurs.

Limbs

Recent studies showcase that Trucidocynodon not only had erect limbs, but it also possibly had digitigrade forelimbs, being among the first synapsids to show adaptations for cursoriality, though it wasn't as specialised a runner as modern cursorial mammals like ungulates.