Colognathus

Colognathus Temporal range: Triassic [1] PreꞒ Ꞓ O S D C P T J K Pg N
Scientific classification
Kingdom:	Animalia
Phylum:	Chordata
Class:	Reptilia
Subclass:	?Anapsida
Order:	?Procolophonidae
Genus:	Colognathus Case, 1933[1][2]
Species
C. obscurus (Case, 1928)[3]
Synonyms[1][3]
Xenognathus Case, 1928 Xenognathus obscurus Case, 1928[4]

Colognathus is a genus of extinct reptile from Late Triassic rocks of the southwestern United States. It was described in 1928 from a jaw fragment by Case, who interpreted the new taxon as a fish. The type species is C. obscurus.

Distribution

Approximately 25 specimens have been found as of 2007.^[5] A great many of the reptile's fossils are from the Tecovas Formation of western Texas. Other finds of Colognathus were from places such as the Palo Duro Canyon (in western Texas) and the Santa Rosa Formation (in New Mexico).^[5] One tooth is known from the Blue Mesa Member of the Chinle Formation at Petrified Forest National Park, Arizona. Material from the Middle Triassic (Ladinian) Lower Keuper of southern Germany has been assigned to Colognathus, extending the temporal range of the form in the Middle Triassic.^[6]

Classification

Colognathus was originally named Xenognathus by Ermine Cowles Case in 1928,^[4] but that name was preoccupied, so Case provided the replacement name Colognathus in 1933.^[2] Researchers have classified Colognathus as a reptile, although its lower-level classification remains uncertain, although it may be a procolophonid.^[5][7]

References

1. "†Colognathus Case 1933". Paleobiology Database. Fossilworks. Retrieved 24 February 2022.
2. Case, E. C. (1933). "Colognathus proposed for Xenognathus, preoccupied". Contributions from the Museum of Paleontology, University of Michigan. 3 (1): 65. JSTOR 24530279.
3. "†Colognathus obscurus Case 1928". Paleobiology Database. Fossilworks. Retrieved 24 February 2022.
4. Case, E. C. (1928). "Indications of a cotylosaur and of a new form of fish from the Triassic beds of Texas, with remarks on the Shinarump Conglomerate". Journal of the Washington Academy of Sciences. 23 (1): 65. hdl:2027.42/48181.
5. Heckert, Andrew B. (2007). "Colognathus obscurus Case, an unusual vertebrate index fossil of Adamanian (St. Johnsian: Latest Carnian) time, from the Upper Triassic of the American Southwest". Geological Society of America Abstracts with Programs. 2007 GSA Denver Annual Meeting (28–31 October 2007). Vol. 39. p. 30.
6. Sues, Hans-Dieter; Schoch, Rainer R. (2013). "First record of Colognathus (?Amniota) from the Middle Triassic of Europe". Journal of Vertebrate Paleontology. 33 (4): 998–1002. Bibcode:2013JVPal..33..998S. doi:10.1080/02724634.2013.732977. S2CID 83951152.
7. Schoch, Rainer R. (2011). "A procolophonid-like tetrapod from the German Middle Triassic". Neues Jahrbuch für Geologie und Paläontologie - Abhandlungen. 259 (2): 251–255. doi:10.1127/0077-7749/2011/0124.