Bruce A. Schumacher

Michael J. Everhart

Academic paper

Paludicila

5

2

33-54

The old �Fort Benton Group� (Middle Cenomanian to Middle Turonian) in central Kansas has produced a relatively large number of plesiosaur specimens. In modern terminology, this historical stratigraphic term refers to the Graneros Shale, Greenhorn Limestone, and Carlile Shale of the Western Interior. In particular, the Fairport Chalk Member of the Carlile Shale has produced an unusually high number of partial plesiosaur skeletons in light of the fact that it is characteristically poorly exposed and minimally accessible. Polycotylids, including Trinacromerum bentonianum, are first documented in central Kansas from the upper Hartland Shale Member, Greenhorn Limestone (middle Upper Cenomanian), and appear to be especially well represented in the upper Greenhorn Limestone and lower one-half of the Fairport Chalk (Lower and Middle Turonian). Pliosaurids, including Brachauchenius lucasi, are known from the basal Lincoln Limestone Member, Greenhorn Limestone (Middle Cenomanian) to the middle of the Fairport Chalk. The occurrence of pliosaurs in the Fairport Chalk (early Middle Turonian) is at or near the last known occurrence of this group prior to their extinction. Elasmosaurid remains are rare throughout the �Fort Benton� interval, with only three firmly established records from the Graneros Shale and Greenhorn Limestone (Middle Cenomanian to Early Turonian) in Kansas.

English