Araeoscelis

From Wikipedia, the free encyclopedia

Araeoscelis
Temporal range: Artinskian 284.4–275.6 Ma
Life restoration
Scientific classification Edit this classification
Domain: Eukaryota
Kingdom: Animalia
Phylum: Chordata
Class: Reptilia
Order: Araeoscelidia
Family: Araeoscelidae
Genus: Araeoscelis
Williston 1910
Type species
Araeoscelis gracilis
Williston 1910
Species
  • A. casei (Broom 1913)
  • A. gracilis Williston 1910
Synonyms
  • Ophiodeirus Broom 1913

Araeoscelis (from Greek: αραιά araiá, 'thin' and Greek: σκελίς skelís, 'ribs of beef')[1] is an extinct genus of reptile, and potentially one of the earliest diapsids (a study from 2022 argued for a placement as a stem-amniote).[2] Fossils have been found in the Nocona, Arroyo and Waggoner Ranch Formations in Texas, dating to the Early Permian. Two species have been described, A. casei and A. gracilis.[3]

Description[edit]

1914 restoration by Samuel Wendell Williston

Araeoscelis was around 60 centimetres (2.0 ft) long, and superficially resembled a modern lizard. It differed from earlier forms, such as Petrolacosaurus, in that its teeth were larger and blunter; possibly they were used for cracking insect carapaces.[4]

Unlike its close relatives, which exhibit the two pairs of skull openings characteristic of diapsids, in Araeoscelis the lower pair of temporal fenestrae were closed with bone, resulting in a euryapsid condition. This would have made the skull more solid, presumably allowing a more powerful bite.[4]

Ichnology[edit]

Footprints found in Nova Scotia have been attributed to Araeoscelis or a close relative.[3]

References[edit]

  1. ^ Colbert, Edwin H. (Edwin Harris); Knight, Charles Robert (1951). The dinosaur book : the ruling reptiles and their relatives. New York : Published for the American Museum of Natural History by McGraw-Hill. p. 145. Retrieved 17 December 2022.
  2. ^ Simões, Tiago R.; Kammerer, Christian F.; Caldwell, Michael W.; Pierce, Stephanie E. (2022-08-19). "Successive climate crises in the deep past drove the early evolution and radiation of reptiles". Science Advances. 8 (33). doi:10.1126/sciadv.abq1898. ISSN 2375-2548. PMC 9390993. PMID 35984885.
  3. ^ a b Dixon, Dougal (2015). The Complete Illustrated Encyclopedia of Dinosaurs. London: Hermes House.
  4. ^ a b Palmer, D., ed. (1999). The Marshall Illustrated Encyclopedia of Dinosaurs and Prehistoric Animals. London: Marshall Editions. p. 82. ISBN 1-84028-152-9.

Further reading[edit]