A new species of the carnivorous cynodont Chiniquodon (Cynodontia, Chiniquodontidae) from the Namibian Triassic

Abstract

Chiniquodontidae is a family of Triassic carnivorous cynodonts well represented in the Middle–Upper Triassic of Argentina and Brazil and, more recently, discovered in Madagascar and central Namibia. The Namibian specimen was found in the uppermost levels of the upper Omingonde Formation and is represented by the skull and partial skeleton. In this contribution, we provide a diagnosis for Chiniquodon omaruruensis, sp. nov., describe the postcranial material, and compare it with that of South American Chiniquodon specimens. Chiniquodon omaruruensis provides the first evidence of elements from the pes in Chiniquodon, and one of the few for non-mammaliaform cynodonts. Chiniquodonomaruruensis has a remarkably large calcaneus with an incipiently differentiated tuber, metatarsal II lateromedially robust but remarkably shorter than metatarsal IV, and an almost quadrangular basal phalanx in digit III. Similar to other Chiniquodon species, it lacks costal plates on ribs and shows a tall and slender scapular blade, a large acromion process positioned well above the scapular neck, and the absence of disc-like phalanges in the autopodium.