Ponerosteus

Ponerosteus Temporal range: Upper Cretaceous
Fossil bone of Ponerosteus (National Museum in Prague)
Scientific classification
Kingdom:	Animalia
Phylum:	Chordata
Class:	Sauropsida
Subclass:	Diapsida
Infraclass:	Archosauromorpha
Superorder:	incertae sedis
Genus:	Ponerosteus Olshevsky, 2000
Species
P. exogyrarum (Fritsch, 1878 [originally Iguanodon exogirarum]) (type species)

Ponerosteus is a dubious genus of archosaur which was first identified as "Iguanodon exogirarum" by Antonín Frič in 1878 for a specimen from the Cenomanian (Late Cretaceous of the Czech Republic, near Holubice by Kralupy nad Vltavou). He later (1905) renamed it Procerosaurus, unaware that this name was already in use (von Huene, 1902). It was renamed Ponerosteus exogyrarum (species name amended) by George Olshevsky in 2000; however, the taxon is considered a nomen dubium by most, as the type material is extremely poor, being apparently an internal cast of a tibia from an animal that may or may not be a dinosaur. The name Ponerosteus can be translated as "bad", "worthless", or "useless bone", which accurately describes the nature of the material.

External links

• George Olshevsky expands on the history of the taxon, on the Dinosaur Mailing List
• Fritsch, 1905. "Synopsis der Saurier der böhm. Kreideformation" [Synopsis of the saurians of the Bohemian Cretaceous formation]. Sitzungsberichte der königlich-böhmischen Gesellschaft der Wissenschaften, II Classe. 1905(8), 1-7.