Deinodon

Drawing the Deinodon - teeth; Lithograph by 1860.

• Montana, USA ( Judith River Formation )

• Deinodon horridus Leidy, 1856

Deinodon ( " terrible tooth" ) is a dubious ( doubtful ) genus of dinosaur from the group of Tyrannosauridae. The genus is known only by twelve fragmentary teeth, which come from the Upper Cretaceous strata of the Judith River Formation in Montana (USA). Although no longer used today, is the name Deinodon in the historical research of Tyrannosauridae (formerly Deinodontidae ) is of great importance, and held its way into the popular culture.

Description and history of research

Deinodon was in 1856 named by paleontologist Joseph Leidy, on the basis of teeth has discovered near the Chouteau County geologist Ferdinand Vandeveer Hayden Missouri River. The type species is Deinodon horridus. It was the first named representative Tyrannosauridae. Leidy described Deinodon as a reptile from the group of Sauria; the description included a few paragraphs. Together with Deinodon named Leidy three other dinosaurs - Trachodon, Troodon and Palaeoscincus; , these were the first dinosaurs that were named from North America.

The teeth were high in the full state probably about 5 cm; so was Deinodon a smaller representative of the tyrannosaurids. Leidy noted that nine of the teeth resemble those of Megalosaurus: You were laterally flattened, curved sound like and equipped with serrated cutting edges. However, the teeth were thicker than those of Megalosaurus. Three other teeth showed a different morphology and were not sound like shape, but were also attributed by Leidy Deinodon since they were together with the other teeth found. Leidy remarked that he had this tooth types assigned to different genera, they are from different sites.

1868 Leidy limited the genus Megalosaurus Deinodon to the nine - like teeth and put the three remaining teeth into the new, independent genus Aublysodon. Both Aublysodon and Deinodon were attributed in the following years several other species; the genera formed the basis of the families Aublysodontidae and Deinodontidae. The Deinodontidae were attributed to genera such as Albertosaurus, Gorgosaurus, Dryptosaurus and Tyrannosaurus. Both families are no longer used today: The Deinodontidae was abolished in favor of the later designation Tyrannosauridae; at Aublysodon and Aublysodontidae it might be to young animals of other tyrannosaurids.

Already Matthew and Brown showed that the teeth can not be different from those of the genus Gorgosaurus. Dale Russell (1970) and several later authors declared Deinodon eventually. Dubium as a noun ( dubious name), lack of delineation from other genres Ashok Sahni (1972 ) suggested to consider Gorgosaurus a junior synonym of Deinodon - as the name Deinodon is older, he would, according to the International Rules for Zoological Nomenclature priority; the name Gorgosaurus would be invalid.