Ustia (therapsid)

Ustia
Temporal range: Middle Permian
Scientific classification Edit this classification
Domain: Eukaryota
Kingdom: Animalia
Phylum: Chordata
Clade: Synapsida
Clade: Therapsida
Suborder: Biarmosuchia
Genus: Ustia
Ivachnenko, 2003
Type species
Ustia atra
Ivachnenko, 2003

Ustia is an extinct genus of biarmosuchian therapsids from the Middle Permian of Russia. It is known from a single species, Ustia atra, which was described in 2003 from an isolated lower jaw. Ustia was classified in the family Ictidorhinidae, which also includes the genus Ictidorhinus from South Africa. Both are relatively small biarmosuchians.[1] Several other Russian therapsids known only from lower jaw bones have been placed in Ictidorhinidae, and the family is likely a paraphyletic assemblage representing a small body type than a true clade.[2]

  1. ^ Ivakhnenko, M. F. (2008). "Cranial morphology and evolution of Permian Dinomorpha (Eotherapsida) of eastern Europe". Paleontological Journal. 42 (9): 859–995. doi:10.1134/S0031030108090013.
  2. ^ Sidor, C. A. (2003). "The Naris and Palate of Lycaenodon Longiceps (Therapsida: Biarmosuchia), with Comments on Their Early Evolution in the Therapsida". Journal of Paleontology. 77 (5): 977–984. doi:10.1666/0022-3360(2003)077<0977:TNAPOL>2.0.CO;2.