Named By: P. E. Olsen - 1979.
Classification: Chordata, Reptilia, Protorosauria, Tanystropheidae.
Species: T. ahynis (type).
Size: Roughly about 50-60 centimetres long.
Known locations: USA, Arizona - Chinle Formation, New Jersey - Lockatong Formation, and North Carolina - Cow Branch Formation.
Time period: Norian of the Triassic.
Fossil representation: Several individuals.
Tanytrachelos is a genus of tanystropheiid reptile (relative of Tanystropheus) that lived during the Late Triassic. There is speculation that Tanytrachelos may be synonymous with the genus Gwyneddosaurus, and usually this would mean Tanytrachelos would be renamed as Gwyneddosaurus since this genus was named before Tanytrachelos. However since Gwyneddosaurus is based upon very dubious fossil remains, there has also been suggestion that if the two genera indeed are synonymous, then a special case should be made to preserve Tanytrachelos as a valid genus since it is the only one based upon good identifiable remains.
- A new aquatic eosuchian from the Newark Supergroup (Late Triassic–Early Jurassic) of North Carolina and Virginia. - Postilla 176:1-14. - P. E. Olsen - 1979.
- Multivariate morphometrics and allometry of the Triassic reptile Tanytrachelos ahynis. - Geological Society of America Abstracts with Programs 37 (7): 88. M. Casey - 2005.
- Quantitative Taphonomy of a Triassic Reptile Tanytrachelos ahynis from the Cow Branch Formation, Dan River Basin, Solite Quarry, Virginia. - PALAIOS 22 (6): 598. - M. M. Casey, N. C. Fraser & M. Kowalewski - 2007.
- A complete and articulated Tanytrachelos ahynis (Reptilia: Protorosauroidea) from the Late Triassic Lockatong Formation of northern New Jersey, U.S.A. - Jason Schein, David C. Parris & Rodrigo Pellegrini - 2010.
- The middle-late Triassic tetrapod footprint ichnogenus Gwyneddichnium. - New Mexico Museum of Natural History & Science Bulletin. 62: 135–156. - Spencer G. Lucas, Michael J. Szajna, Martin G. Lockley, David L. Fillmore, Edward L. Simpson, Hendrik Klein, Jack Boyland & Brian W. Hartline - 2014.