page_title: Doswellia
section_title: Jaw functionality
hierarchical_section_title: Doswellia / Paleobiology / Jaw functionality
caption_attribution_description: English: A ventral view of the posterior skull of USNM 214823, the paratype specimen of Doswellia kaltenbachi
context_page_description: Doswellia is an extinct genus of archosauriform from the Late Triassic of North America. It is the most notable member of the family Doswelliidae, related to the proterochampsids. Doswellia was a low and heavily built carnivore which lived during the Carnian stage of the Late Triassic. It possesses many unusual features including a wide, flattened head with narrow jaws and a box-like rib cage surrounded by many rows of bony plates. The type species Doswellia kaltenbachi was named in 1980 from fossils found within the Vinita member of the Doswell Formation in Virginia. The formation, which is found in the Taylorsville Basin, is part of the larger Newark Supergroup. Doswellia is named after Doswell, the town from which much of the taxon's remains have been found. A second species called D. sixmilensis was described in 2012 from the Bluewater Creek Formation of the Chinle Group in New Mexico; however, this species was subsequently transferred to the separate doswelliid genus Rugarhynchos.
context_section_description: The quadratojugal and surangular bones (on the cranium and lower jaw, respectively) were both incorporated into the jaw joint, reinforcing the joint and preventing side-to-side or front-to back movement. As a result, the jaws of Doswellia would have been incapable of any notable form of movement other than vertical scissor-like snapping. In addition, the expanded back of the skull and very deep rear part of the lower jaw likely housed muscles that could let the jaw both open and close with a high amount of force. This contrasts with modern crocodilians, which have a powerful bite but a much weaker ability to open their jaws. Nevertheless, the high amount of sculpturing in the skull of Doswellia is similar to the skulls of modern crocodilians. It is likely an adaptation to minimize stresses in the skull during a powerful bite.
caption: The paratype skull of Doswellia kaltenbachi, seen from below.
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