Scientific Illustration

rhamphotheca:

Thrinaxodon

… a genus of cynodont therapsid that lived during the Triassic Period (248-245 million years ago) notable for being a transitional fossil.The two known species ranged in size from that of a small badger (50 cm) to ermine-sized (30 cm long).Pits on the skull suggest that Thrinaxodon may have had whiskers, but whether it also had fur is debated, though it likely had a near-mammalian warm-blooded metabolism. Even so, Thrinaxodon still laid eggs, and there were many reptilian features in its skeleton.

Its remains were found on South Africa and Antarctica, supporting the notion that the two continents were once joined together. Its name was taken from Greek θρῖναξ “trident, three-pronged fork” and ὀδούϛ ὀδόντ- “tooth” in reference to it’s cheek teeth, but with a Greek language error: “Thrinacodon” would have been the grammatically correct form…

(read more: Wikipedia)    

(images: T - from Ostrom, J. H. 1992. A history of vertebrate success. Pp. 119-139. In, Schopf, J. W. (ed.) Major Events in the History of Life., BL - Nobu Tamura, BR - Claire H.)