Oromycter

Oromycter; Temporal range: Early Permian 290.1–268 Ma PreꞒ Ꞓ O S D C P T J K Pg N
Scientific classification
Domain:	Eukaryota
Kingdom:	Animalia
Phylum:	Chordata
Clade:	Synapsida
Clade:	†Caseasauria
Family:	†Caseidae
Genus:	†Oromycter; Reisz, 2005
Type species
	Oromycter dolesorum; Reisz, 2005

Oromycter is an extinct genus of caseid synapsids from the Early Permian of Oklahoma. The sole and type species, Oromycter dolesorum, was named in 2005 by Robert R. Reisz.^[1]^[2]

Description

Oromycter was a small caseid characterized by its dentition, which lacked the distinct leaf-like serrations of other caseids and instead possessed broad, spatulate and roughened cutting edges. Its teeth were also more thoroughly attached to the bone of the skull and jaw than in other members of Caseidae. The first and second teeth of the premaxilla show distinct wear facets which suggest that they occluded with the first and second teeth of the dentary, possibly to facilitate the cropping of vegetation. Its lacrimal bone, while clearly caseid in form, appears more primitive than in any other known caseid.^[1]

Classification

Oromycter is the oldest and most basal caseid known, and is the sister taxon of all other caseids.

Below is a cladogram based on the phylogenetic analysis of Maddin et al. in 2008.^[3]

Caseidae

Oromycter dolesorum

Casea broilii

"Casea rutena" (now Euromycter rutenus)

Ennatosaurus tecton

	Cotylorhynchus romeri

	Angelosaurus dolani

References

^ ^a ^b Reisz, R. R. 2005. Oromycter, a New Caseid from the Lower Permian of Oklahoma. Journal of Vertebrate Paleontology 25 (4): 905-910.
^ "Oromycter". Fossilworks. Retrieved 17 December 2021.
^ Maddin, Hillary C.; Sidor, Christian A.; Reisz, Robert R. (2008-03-12). "Cranial anatomy of Ennatosaurus tecton (Synapsida: Caseidae) from the Middle Permian of Russia and the evolutionary relationships of Caseidae". Journal of Vertebrate Paleontology. 28 (1): 160–180. doi:10.1671/0272-4634(2008)28[160:CAOETS]2.0.CO;2. ISSN 0272-4634.