Desmatosuchus

Desmatosuchus (, from Greek δεσμός desmos 'link' + σοῦχος soûkhos 'crocodile') is an extinct genus of archosaur belonging to the Order Aetosauria. It lived in North America and potentially India (cf. Desmatosuchus) during the Late Triassic.

==Description== thumb|left|D. spurensis compared to a human Desmatosuchus was a large quadrupedal reptile measuring to over long and weighing about . Its vertebral column had amphicoelous centra and 3 sacral vertebrae. This archosaur's most distinguishing anatomical characteristics were its scapulae which possessed large acromion processes commonly referred to as "shoulder spikes". The forelimbs were much shorter than the hindlimbs, with humeri less than two-thirds the length of the femurs. The pelvic girdle consisted of a long pubis with a strong symphysis in the middle, a plate-like ischium, a highly recurved ilium, and a deep, imperforate acetabulum. The femurs were relatively long and straight, the ankles crurotarsal, with calcaneal tubers that gave it large heels. left|thumb|Desmatosuchus skeleton on display at the University of Michigan Museum of Natural History Its skull was relatively small, on average about 37 centimeters long, 18 centimeters wide, and 15 centimeters high. The braincase was very firmly fused with the skull roof and palate. It had slender, forked premaxillae that turned up and expanded in the front, creating a shovel-like structure. Desmatosuchus is unique among aetosaurs in that its species are the only known aetosaurs that lacked teeth on their premaxillae. Their premaxillae fit loosely together with their maxillae, indicating flexibility at that joint. Their maxilla contained 10 to 12 teeth. Desmatosuchus also had very thin vomers, which bounded the medial side of the internal nares. These internal nares were relatively large, roughly half the length of the entire palate. The lower jaw typically carried 5 or 6 teeth, and had a toothless beak on the end. The dentary was about half the length of the lower jaw, with the front portion being toothless and covered by a horny sheath. Behind the dentary was a moderately large mandibular fenestra.