Desmatosuchus

Extinct genus of reptiles

Desmatosuchus (/d//ɛ//z//m//æ//t//oʊ//s//uː//k//ə//s/, from Greek δεσμός desmos 'link' + σοῦχος soûkhos 'crocodile') is an extinct genus of archosaur belonging to the Order Aetosauria. It lived during the Late Triassic.

Desmatosuchus was a large quadrupedal reptile measuring to over long and weighing about Its vertebral column had amphicoelus 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 femurs were relatively long and straight, the ankles crurotarsal, with calcaneal tubers that gave it large heels.

The first Desmatosuchus discovery occurred in the late 19th century when E. D. Cope classified armor from the Dockum Group in Texas, USA, as the new species Episcoposaurus haplocerus. Case later classified a partial skeleton found in the Tecovas Formation as Desmatosuchus spurensis. Since the localities of Cope and Case were only a few kilometers apart, the two taxa were synonymized into Desmatosuchus haplocerus, the initial type species of the genus. Desmatosuchus chamaensis is recognized as a distinct genus, but there is some dispute about whether the name Heliocanthus or Rioarribasuchus applies.

Bones and armor pieces of Desmatosuchus are abundant in the Dockum formation, Chinle formation, and Post quarry, indicating that they were widespread and abundant during the Late Triassic. It is believed that Desmatosuchus dug for food in the soft mud near bodies of water due to the abundance of lakes and rivers in the Dockum area and the fact that Desmatosuchus scutes are often found among parts of other reptiles that are known to have fed along waterways. Desmatosuchus possessed both of these features, along with its long femur and elongate pubis, making it more mobile than most thecodonts of its time. For instance, both groups are armored. They possess long snouts that lack teeth on the end. Also, there is evidence of bees, wasps, and termites in the Late Triassic, meaning that Desmatosuchus had access to insects that armadillos prey on. Their teeth are somewhat similar in shape, although armadillos have more peg like teeth. Both Desmatosuchus and armadillos typically carry around 6 teeth on their dentaries. Both armadillos and Desmatosuchus have hypertrophied processes present on their limb bones, which indicates large limb muscles. This connection is more tenuous, however, since Desmatosuchus have a crest over their hind limbs but lack one on their forelimbs, meaning that they likely didn't have the musculature for digging with their forelimbs the way armadillos do. In spite of these parallels, the general consensus is still that Desmatosuchus was most likely herbivorous.