New archosauriform remains from the German Lower Keuper

Isolated bones of archosauriforms form regular finds in deposits of the Lower Keuper (Erfurt Formation: upper Middle Triassic) of southwestern Germany. In addition to the fairly well known 3-5 m long rauisuchian Batrachotomus kupferzellensis and the very fragmentary Zanclodon laevis, remains of further, 1-2 m long archosauriforms have been identified. Although the number of taxa represented by this incomplete material is unknown, the distinctness of these finds from Batrachotomus and Zanclodon is indicated by the following features: (1) a rauisuchian type maxilla with well-developed interdental plates, which forms a long suture with a posterodorsal process of the premaxilla, (2) relatively long cervical and anterior dorsal vertebrae, (3) a gracile humerus with a narrow proximal head and a weak deltopectoral crest, (4) a slender and markedly curved tibia, and (5) tear-drop shaped, keeled armour plates. These findings highlight the diversity of large predators in Middle Triassic land vertebrate faunas of Central Europe.