Thalassomedon

Genus

Thalassomedon

Author

Welles, 1943

Classification

Sauropterygia
Eosauropterygia
Eusauropterygia
Pistosauroidea
Pistosauria
Plesiosauria
Plesiosauroidea
Elasmosauridae

Age

Cenomanian

Location

Near Pritchet, northwestern Baca County, Colorado, USA

Type species

Thalassomedon haningtoni

Other species

None

Referred material

To compile

The holotype of Thalassomedon was discovered by R. L. Landberg in 1939 in Baca County, Colorado. Thalassomedon has a short and deep atlas-axis and 62 cervical vertebrae, and there is no pectoral or pelvic bar in the adult condition (Carpenter, 1999). The species name haningtoni is sometimes wrongly spelled ‘hanningtoni’ (as in Carpenter 1999) or ‘haringtoni’ (as in the AMNH exhibit).

The three dimensional skull used in mounted skeletons of this taxon in the AMNH (American Museum of Natural History, New York) and DMNH (Denver Museum of Natural History) is a reconstruction based on the crushed holotype specimen.

Carpenter (1999) synonymized Alzadosaurus with Thalassomedon. Thalassomedon haningtoni Welles, 1943, is the type and only known species of this genus.

Thalassomedon (AMNH 29878), American Museum of Natural History, New York
Thalassomedon (AMNH 29878), American Museum of Natural History, New York
Thalassomedon (AMNH 29878), American Museum of Natural History, New York
Thalassomedon, American Museum of Natural History, New York
Thalassomedon (AMNH 29878), American Museum of Natural History, New York
Thalassomedon (AMNH 29878), American Museum of Natural History, New York