Globidens

Globidens ("Globe teeth") is an extinct genus of mosasaur lizard.

Globidens alabamaensis was first described by Gilmore (1912). A second species (G. dakotensis) was described by Russell (1975). The third North American species (G. schurmanni) was added by Martin (2007)

Description
Globidens was ~6 m (20 ft) in length and in appearance very much like other mosasaurs (streamlined body with flippers, a laterally flattened tail and powerful jaws). The teeth of Globidens were vastly different from other mosasaurs, as they were globular, as suggested in its generic name. Generally, most mosasaurs had sharp teeth evolved to grab soft, slippery prey like fish and squid, which, in later species, were later modified to rend flesh, as well. While many other mosasaurs were capable of crushing the shells of ammonites, none were as specialized in dealing with armored prey like Globidens. Globidens, unlike most other mosasaurs, had semispherical teeth with rounded nubbin-like points, which were much better suited for crushing tough armored prey like small turtles, ammonites, nautili, and bivalves. Like its larger relative, Mosasaurus, Globidens had a robustly built skull with tightly-articulating jaws. Such features no doubt played a large role in its ability to penetrate the armor of its shelled prey.

Classification
The smaller genus Carinodens is regarded as a sister taxon of Globidens.

Cladogram of mosasaurs and related taxa modified from Aaron R. H. Leblanc, Michael W. Caldwell and Nathalie Bardet, 2012: