Named By: O'Keefe and Wahl - 2003.
Synonyms: Cimoliasaurus laramiensis, Tricleidus laramiensis.
Classification: Chordata, Reptilia, Sauropterygia, Plesiosauria, Cryptoclididae, Aristonectidae.
Species: T. laramiensis (type).
Size: Around 2 meters long.
Known locations: USA, Wyoming - Sundance Formation.
Time period: Oxfordian of the Jurassic.
Fossil representation: Partial skeletal remains and elements of the skull.
pertaining to Tatenectes were originally assigned
as a species of
(C. laramiensis) by W. C. Knight in
Then in 1912 they were moved over to Tricliedus
laramiensis) by Mehl. Then in 2003 fossils
pertaining to this
species were established as a new genus by O'Keefe and Wahl. However
the original holotype fossils used by knight to name C.
are now lost and neotypes of partial skeletons (UW 12543
& UW 24801) are now the established base of this genus.
Tatenectes was a small plesiosaur with a body proportionately flatter than many other genera. This may have been an environmental adaptation since the Sundance Formation is interpreted as being the bed of a shallow sea during the Jurassic, an area that was probably not suitable for large plesiosaur forms. Tatenectes is usually classified within the Cryptoclididae group of plesiosaurs (those like Cryptociedus), however there is also occasionally placement within the Aristonectidae (those similar to Aristonectes) by some researchers.