Brachauchenius

Brachauchenius (meaning 'short neck') is an extinct genus of pliosaurid that lived in America (USA and Colombia) during the Cretaceous.

The type species, Brachauchenius lucasi, lived in the Western Inland Sea of North America around 93.5-89.3 million years ago, during the Turonian stage of the Cretaceous. An older specimen referred to Brachauchenius from the Barremian of Colombia represents the first re-occurrence of the non-rhomaleosaurid pliosaurs after a Berriasian-Hauterivian hiatus.

The first known (type) specimen (USNM 4989) was collected by Charles Hazelius Sternberg from Ottawa County, Kansas in 1884.[3][4] It had a skull length of about 90 cm. The species was named by Samuel W. Williston.[1][5] Brachauchenius represents the last known occurrence of a pliosaur in North America.

A larger specimen (FHSM VP-321 - skull length 170 cm) was collected by George Fryer Sternberg in 1952 from the Fairport Chalk of Russell County, Kansas, and later described by Carpenter.[6] Schumacher and Everhart (2005) reported on the age and locality of both Kansas specimens.[7] This pliosaur grew to around 10 meters (30 ft) in length. This specimen was reassigned to its own genus and species, Megacephalosaurus eulerti.[