Elginia

Elginia was a pareiasaur; a member of a group of Late Permian parareptiles which may have grown up to 60 centimetres (2.0 ft). It was named for the area around Elgin in Scotland, which has yielded many fossils referred to as the Elgin Reptiles.

Elginia
Temporal range: Changhsingian, 254–252 Ma
↓
Restoration of Elginia mirabilis
Scientific classification
Kingdom:
Animalia
Phylum:
Chordata
Class:
Reptilia
Order:
Procolophonomorpha
Family:
†Pareiasauridae
Subfamily:
†Elgininiinae
Genus:
†Elginia

Newton, 1893
Type species
†Elginia mirabilis
Newton, 1893
Other species
  • Elginia wuyongae, Liu & Bever, 2018

Description
Reconstruction of the head of E. mirabilis
Elginia mirabilis skull cast

Elginia was a dwarf genus of pareiasaur, only about 60 centimetres (2 ft) long, with fossils found in the Hopeman Sandstone Formation near Elgin, Scotland (E. mirabilis) and the Naobaogou Formation in Inner Mongolia, China (E. wuyongae).[1] The type species, E. mirabilis, is known only from a single skull, which is about 15 cm long, triangular, coarsely sculptured, and armed with a number of paired bosses or spines, with the longest pair growing out of the back of the skull. These spikes were probably used for display rather than physical combat.[2] The upper jaw bears 12 pairs of teeth, each with 9 or 10 cusps. The teeth are slightly constricted at the base and serrated at the crown.

Classification

As with many pareiasaurs, precise phylogenetic placement is uncertain. Elginia shares with Scutosaurus elaborate cranial ornament, which has been used to suggest the two were closely related.[3] Elginia has also been hypothesized to share a relationship with the more basal taxon Dolichopareia (=Nochelesaurus) on the basis of a deeply notched skull table shared with the latter,[4] however other authors have argued that this association was based on taphonomic distortion.[5] Cladistic analyses have tended to nest Elginia deeper among pareiasaurs, making it more derived than the earlier giant Pareiasaurus and Scutosaurus. The placement of Elginia remains volatile, with the taxon hopping between more apical pareiasaurs such as Therischian[5][6] and more basal pareiasaurs such as Scutosaurus and pumiliopareiasaurs.[7]

References
  1. Liu, Jun; Bever, Gabriel S. (May 2018). Angielczyk, Kenneth (ed.). "The tetrapod fauna of the upper Permian Naobaogou Formation of China: a new species of Elginia (Parareptilia, Pareiasauria)". Papers in Palaeontology. 4 (2): 197–209. doi:10.1002/spp2.1105.
  2. Palmer, D., ed. (1999). The Marshall Illustrated Encyclopedia of Dinosaurs and Prehistoric Animals. London: Marshall Editions. p. 64. ISBN 1-84028-152-9.
  3. Boonstra, L.D. (1932). "The Phylogenesis of the Pareiasauridae: A Study in Evolution". South African Journal of Science. 29: 480–486.
  4. Walker, A. D. (1973). "The age of the Cuttie's Hillock Sandstone (Permo-Triassic) of the Elgin area". Scottish Journal of Geology. 9 (3): 177–183. doi:10.1144/sjg09030177.
  5. Lee, M.S.Y. (1997). "Pareiasaur phylogeny and the origin of turtles". Zoological Journal of the Linnean Society. 120 (3): 197–280. doi:10.1006/zjls.1997.0080.
  6. Jalil, Nour-Eddine; Janvier, Philippe (2005). "Les pareiasaures (Amniota, Parareptilia) du Permien supérieur du Bassin d'Argana, Maroc". Geodiversitas (in French). 27 (1): 35–132.
  7. Tsuji, Linda A.; Müller, Johannes (2009). "Assembling the history of the Parareptilia: phylogeny, diversification, and a new definition of the clade". Fossil Record. 12 (1): 71–81. doi:10.1002/mmng.200800011.
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