Ponerosteus
Encyclopedia
Ponerosteus is a dubious genus
of archosaur
which was first identified as "Iguanodon
exogirarum" by Antonin Fritsch
in 1878 for a specimen from the Cenomanian
(Late Cretaceous
of the Czech Republic
). 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.
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.
Genus
In biology, a genus is a low-level taxonomic rank used in the biological classification of living and fossil organisms, which is an example of definition by genus and differentia...
of archosaur
Archosaur
Archosaurs are a group of diapsid amniotes whose living representatives consist of modern birds and crocodilians. This group also includes all extinct non-avian dinosaurs, many extinct crocodilian relatives, and pterosaurs. Archosauria, the archosaur clade, is a crown group that includes the most...
which was first identified as "Iguanodon
Iguanodon
Iguanodon is a genus of ornithopod dinosaur that lived roughly halfway between the first of the swift bipedal hypsilophodontids and the ornithopods' culmination in the duck-billed dinosaurs...
exogirarum" by Antonin Fritsch
Antonin Fritsch
Antonin Fritsch was a Czech paleontologist, biologist and geologist, living during the Austria–Hungary era. Professor at the Charles University and later became director of the National Museum in Prague...
in 1878 for a specimen from the Cenomanian
Cenomanian
The Cenomanian is, in the ICS' geological timescale the oldest or earliest age of the Late Cretaceous epoch or the lowest stage of the Upper Cretaceous series. An age is a unit of geochronology: it is a unit of time; the stage is a unit in the stratigraphic column deposited during the corresponding...
(Late Cretaceous
Late Cretaceous
The Late Cretaceous is the younger of two epochs into which the Cretaceous period is divided in the geologic timescale. Rock strata from this epoch form the Upper Cretaceous series...
of the Czech Republic
Czech Republic
The Czech Republic is a landlocked country in Central Europe. The country is bordered by Poland to the northeast, Slovakia to the east, Austria to the south, and Germany to the west and northwest....
). He later (1905) renamed it Procerosaurus
Procerosaurus
Procerosaurus is the name given to an invalid genus of dinosaur.There are two Procerosaurus specimens:*The first was described as P...
, unaware that this name was already in use (von Huene
Friedrich von Huene
Friedrich von Huene was a German paleontologist who named more dinosaurs in the early 20th century than anyone else in Europe.-Biography:...
, 1902). It was renamed Ponerosteus exogyrarum (species name amended) by George Olshevsky
George Olshevsky
George Olshevsky is a freelance editor, writer, publisher, amateur paleontologist, and mathematician living in San Diego, California.Olshevsky maintains the comprehensive online Dinosaur Genera List...
in 2000; however, the taxon
Taxon
|thumb|270px|[[African elephants]] form a widely-accepted taxon, the [[genus]] LoxodontaA taxon is a group of organisms, which a taxonomist adjudges to be a unit. Usually a taxon is given a name and a rank, although neither is a requirement...
is considered a nomen dubium
Nomen dubium
In zoological nomenclature, a nomen dubium is a scientific name that is of unknown or doubtful application...
by most, as the type
Holotype
A holotype is a single physical example of an organism, known to have been used when the species was formally described. It is either the single such physical example or one of several such, but explicitly designated as the holotype...
material is extremely poor, being apparently an internal cast of a tibia
Tibia
The tibia , shinbone, or shankbone is the larger and stronger of the two bones in the leg below the knee in vertebrates , and connects the knee with the ankle bones....
from an animal that may or may not be a dinosaur
Dinosaur
Dinosaurs are a diverse group of animals of the clade and superorder Dinosauria. They were the dominant terrestrial vertebrates for over 160 million years, from the late Triassic period until the end of the Cretaceous , when the Cretaceous–Paleogene extinction event led to the extinction of...
. 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
- Dinosauromorpha
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.