A short-snouted trematosauroid (Tetrapoda,Temnospondyli) from the Early Triassic of Australia: the oldest known trematosaurine

The trematosauroid temnospondyl Tirraturhinus smisseni gen. et sp. nov. from the Arcadia Formation of central Queensland, Australia, is described on the basis of its rostrum. This is the first trematosaurine (short-snouted) trematosauroid from Australia, and is considered to be most closely related to Tertrema acuta from Spitzbergen. Tirraturhinus smisseni occurs alongside lonchorhynchine (long-snouted) trematosauroids in the Arcadia Formation; the co-occurrence of both trematosauroid morphotypes in that fauna is repeated in a number of non-marine Early Triassic faunas elsewhere in Pangaea. The Arcadia Formation is probably Griesbachian (earliest Triassic), so that T. smisseni is the oldest known trematosaurine.