| San Angelo Formation | |
|---|---|
| Stratigraphic range: | |
| Type | Formation |
| Unit of | Pease River Group |
| Underlies | Blaine Formation |
| Overlies | Clear Fork Group |
| Location | |
| Region | Texas |
| Country | United States |
The San Angelo Formation is a geologic formation in Texas. It preserves fossils dating back to the Permian period. It is one of the geologically youngest formations to preserve fossils of pelycosaurs.
Stratigraphy and age
The San Angelo Formation belongs to the Kungurian stage of the Cisuralian series. It underlies the Blaine Formation, which is either upper Kungurian or lower Guadalupian.[1][2]
Fossil content
Everett C. Olson regarded the San Angelo Formation as preserving some of the oldest known therapsids, several of which he classified in a taxon he called Eotheriodonta.[3] These taxa are now interpreted as caseids and sphenacodontids, not therapsids.[4]
Color key
|
Notes Uncertain or tentative taxa are in small text; |
Synapsids
| Genus | Species | Location | Material | Notes | Images |
|---|---|---|---|---|---|
| Angelosaurus | A. dolani | A caseid | |||
| Caseoides | C. sanangeloensis | A caseid | |||
| Caseopsis | C. agilis | A caseid | |||
| Cotylorhynchus | C. hancocki | A caseid | |||
| Dimacrodon | D. hottoni | ||||
| Dimetrodon | D. angelensis | A sphenacodontid | |||
| Driveria | D. ponderosa | ||||
| Eosyodon | E. hudsoni | A dubious sphenacodontid[5] | |||
| Gorgodon | G. minutus | ||||
| Knoxosaurus | K. niteckii | ||||
| Mastersonia | M. driverensis | ||||
| Steppesaurus | S. gurleyi | ||||
| Tappenosaurus | T. magnus | ||||
See also
References
Bibliography
- DiMichele, William A.; Mamay, Sergius H.; Chaney, Dan S.; Hook, Robert W.; Nelson, W. John (2001). "An Early Permian flora with Late Permian and Mesozoic affinities from North-Central Texas". Journal of Paleontology. 75 (2): 12.
- Kammerer, Christian F. (2011). "Systematics of the Anteosauria (Therapsida: Dinocephalia)". Journal of Systematic Palaeontology. 9 (2): 261–304. doi:10.1080/14772019.2010.492645. ISSN 1477-2019.
- Lucas, Spencer G; Golubev, Valeriy K (2019). "Age and duration of Olson's Gap, a global hiatus in the Permian tetrapod fossil record". Permophiles: 5.
- Olson, Everett C. (1962). "Late Permian Terrestrial Vertebrates, U. S. A. and U. S. S. R." Transactions of the American Philosophical Society. 52 (2): 1–224. doi:10.2307/1005904. ISSN 0065-9746. JSTOR 1005904.
- Olson, Everett C.; Beerbower, James R. (1953). "The San Angelo Formation, Permian of Texas, and Its Vertebrates". The Journal of Geology. 61 (5): 389–423. doi:10.1086/626109. ISSN 0022-1376. JSTOR 30079693.
- Sidor, C. A.; Hopson, J. A. (1995). "The taxonomic status of the Upper Permian eotheriodont therapsids of the San Angelo Formation (Guadalupian), Texas". Journal of Vertebrate Paleontology. 15 (3A): 53A.
This article is issued from Wikipedia. The text is licensed under Creative Commons - Attribution - Sharealike. Additional terms may apply for the media files.