The first record of the lamniform shark genus, Johnlongia, from the Niobrara Chalk (Upper Cretaceous), western Kansas

Abstract

We describe the first occurrence of the Late Cretaceous lamniform shark, Johnlongia sp. (Elasmobranchii: Odontaspididae), from the Smoky Hill Chalk Member of the Niobrara Chalk in Trego County, Kansas. The specimen, a small isolated tooth, is morphologically unique and may represent a new taxon within the genus. The tooth is from the Upper Coniacian portion of the Smoky Hill Chalk, and represents the stratigraphically youngest Johnlongia specimen in the world. The addition of Johnlongia sp. increases the total number of lamniform species reported from the Smoky Hill Chalk to eight.