Isolated archosaurian remains consisting of pelvic elements and femora from the upper Moenkopi Formation (Middle Triassic) of Arizona are similar to the Late Triassic 'rauisuchians' Chatterjeea and Sillosuchus. The new material is a 'rauisuchian' hypothesized to be more closely related to Chatterjeea and Sillosuchus than to Poposaurus, Arizonasaurus and other rauisuchians. The Moenkopi form material helps polarize characters for a small group of 'rauisuchians'. If current archosaur phylogenies are correct, then the presence of a Chatterjeea-like taxon in the Moenkopi Formation indicates that many of the archosaurian groups radiated by the early Middle Triassic.
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