Priscacara
Priscacara, is a genus of extinct perch described from Early to Middle Eocene fossils. It is characterized by a sunfish-like body and its stout dorsal and anal spines. The genus is best known from the Green River Formation of Wyoming, Utah and Colorado. Mass deaths of Priscacara suggest it formed schools.
Priscacara Temporal range: Eocene | |
---|---|
Priscacara serrata, FMNH PF13014 | |
Scientific classification | |
Kingdom: | |
Phylum: | |
Class: | |
Order: | |
Family: | |
Genus: | Priscacara Cope 1877 |
Species | |
|
History and classification
The type species of Priscacara is P. serrata, described from the holotype specimen, AMNH 2442.[1]
The holotype of P. liops is USNM 4044.[2]
A phylogenetic review of Priscacara by Whitock (2010) recognized only two species, P. serrata and P. liops.[3] P. liops is the most common species of Priscacara within the Green River lacustrine deposits and at certain locations it outnumbers P. serrata by over 3:1. The two species differ in the number of dorsal and anal fin rays, as well as possibly a coarser serrated rear edge of the preopercle in P. serrata. P. liops also has small conical teeth on the pharyngeal jaw, whereas P. serrata has large grinding toothplates, suggesting a diet of snails and crustaceans.[4] A third species, Priscacara aquilonia was described by Wilson (1977) from the Early Eocene "Horsefly shale" of British Columbia.[5]
Priscacara fossils are commonly preserved in the Fossil Lake deposits of Eocene age in westernmost Wyoming, but are rare in the coeval Lake Gossiute sediments of Wyoming and the Lake Uinta deposits of Utah and Colorado. The genus also occurs in the middle Eocene lake deposits of Washington and British Columbia.
References
- Cope, E. D. (1877). "A contribution to the knowledge of the ichthyological fauna of the Green River shales". Bulletin of the United States Geological and Geographical Survey. 3 (4): 807–819.
- Cope, E. D. (1884). "The vertebrata of the Tertiary formations of the West". Report of the United States Geological Survey of the Territories. 3: 1–1009.
- Whitlock, J. A. (2010). "Phylogenetic relationships of the Eocene percomorph fishes Priscacara and Mioplosus". Journal of Vertebrate Paleontology. 30: 1037–1048.
- Grande, L. (1984). "Paleontology of the Green River Formation, with a review of the fish fauna". Geological Survey of Wyoming Bulletin. 63: 1–333.
- Wilson, M. V. (1977). "Middle Eocene freshwater fishes from British Columbia". Life Sciences Contributions, Royal Ontario Museum. 113: 1–66.