''Erectopus'' (meaning "upright foot") is an extinct genus of basal
allosauroid
Allosauroidea is a superfamily or clade of theropod dinosaurs which contains four families — the Metriacanthosauridae, Allosauridae, Carcharodontosauridae, and Neovenatoridae. Allosauroids, alongside the family Megalosauroidea, were among ...
theropod
Theropoda (; ), whose members are known as theropods, is a dinosaur clade that is characterized by hollow bones and three toes and claws on each limb. Theropods are generally classed as a group of saurischian dinosaurs. They were ancestrally c ...
from the
Early Cretaceous
The Early Cretaceous ( geochronological name) or the Lower Cretaceous (chronostratigraphic name), is the earlier or lower of the two major divisions of the Cretaceous. It is usually considered to stretch from 145 Ma to 100.5 Ma.
Geology
Pro ...
La Penthiève Beds Formation of
France
France (), officially the French Republic ( ), is a country primarily located in Western Europe. It also comprises of Overseas France, overseas regions and territories in the Americas and the Atlantic Ocean, Atlantic, Pacific Ocean, Pac ...
and also possibly the
Cernavoda Formation of southern
Romania
Romania ( ; ro, România ) is a country located at the crossroads of Central Europe, Central, Eastern Europe, Eastern, and Southeast Europe, Southeastern Europe. It borders Bulgaria to the south, Ukraine to the north, Hungary to the west, S ...
. The type species is ''E. superbus'', which was initially known as a species of ''
Megalosaurus
''Megalosaurus'' (meaning "great lizard", from Greek , ', meaning 'big', 'tall' or 'great' and , ', meaning 'lizard') is an extinct genus of large carnivorous theropod dinosaurs of the Middle Jurassic period (Bathonian stage, 166 million years ...
''.
Discovery and naming
![Erectopus](https://upload.wikimedia.org/wikipedia/commons/6/6a/Erectopus.jpg)
The holotype, specimen MNHN 2001-4, was discovered between the early 1870s and before 1882 in the
Phosphate
In chemistry, a phosphate is an anion, salt, functional group or ester derived from a phosphoric acid. It most commonly means orthophosphate, a derivative of orthophosphoric acid .
The phosphate or orthophosphate ion is derived from phospho ...
-bearing beds of
La Penthiève (''Mammilatum'' Zone; lower
Albian
The Albian is both an age of the geologic timescale and a stage in the stratigraphic column. It is the youngest or uppermost subdivision of the Early/Lower Cretaceous Epoch/Series. Its approximate time range is 113.0 ± 1.0 Ma to 100.5 ± 0.9 M ...
) at
Louppy-le-Château in eastern France,
[Allain, R. (2005). The enigmatic theropod dinosaur ''Erectopus superbus'' (Sauvage, 1882) from the Lower Albian of Louppy-le-Château (Meuse, France). in Carpenter, K. 2005. ''The Carnivorous Dinosaurs'', Indiana University Press: 72-86.] which have also produced remains of
plesiosaurs,
ichthyosaurs, and
crocodiles. The fossils originally resided in the private collection of Louis Pierson. The first, two teeth and a vertebra, were first described by
Charles Barrois
Charles Eugene Barrois (21 August 18515 November 1939) was a French geologist and palaeontologist.
Life
Barrois was born at Lille and educated at the Jesuit College of St Joseph in that town, where he studied geology under Professor Jules Goss ...
in 1875. After more remains had been found, in 1882
Henri-Émile Sauvage made them the basis for a new
taxon
In biology, a taxon ( back-formation from '' taxonomy''; plural taxa) is a group of one or more populations of an organism or organisms seen by taxonomists to form a unit. Although neither is required, a taxon is usually known by a particular n ...
, ''
Megalosaurus
''Megalosaurus'' (meaning "great lizard", from Greek , ', meaning 'big', 'tall' or 'great' and , ', meaning 'lizard') is an extinct genus of large carnivorous theropod dinosaurs of the Middle Jurassic period (Bathonian stage, 166 million years ...
superbus.''
[Sauvage, H.-É., (1882), "Recherches sur les reptiles trouvés dans le Gault de l'est du bassin de Paris", ''Mémoires de la Société Géologique de France, série 3'' 2(4): 1-42] In 1923, the material was redescribed by
Friedrich von Huene, who argued that it could not be included within the
genus
Genus ( plural genera ) is a taxonomic rank used in the biological classification of extant taxon, living and fossil organisms as well as Virus classification#ICTV classification, viruses. In the hierarchy of biological classification, genus com ...
''Megalosaurus'' and created for the Pierson theropod a separate genus, naming the species ''Erectopus superbus''.
[Huene, F. von, (1923), "Carnivorous Saurischia in Europe since the Triassic", ''Bulletin of the Geological Society of America''34: 449-458] In 1932 von Huene concluded that the original fossils described by Barrois were not necessarily of the same species as the later finds.
[Huene, F. von, (1932). Die fossile Reptil-Ordnung Saurischia, ihre Entwicklung und Geschichte. ''Monographien zur Geologie und Palaeontologie'', ser. 1: 1-361.] Assuming that Sauvage had used the former as the
holotype
A holotype is a single physical example (or illustration) of an organism, known to have been used when the species (or lower-ranked taxon) was formally described. It is either the single such physical example (or illustration) or one of several ...
of ''Megalosaurus superbus'', he therefore created another species: ''Erectopus sauvagei''. Von Huene even declined to use the generic name ''Erectopus'' for the first species, indicating it as "Gen. indeterm. ''superbus''", which however does not constitute a valid name.
Subsequently, the Pierson collection was dispersed after the death of its owner and the holotype was long believed lost to science after
World War II
World War II or the Second World War, often abbreviated as WWII or WW2, was a world war that lasted from 1939 to 1945. It involved the vast majority of the world's countries—including all of the great powers—forming two opposin ...
. However, casts of some of the bones have been located in the
Muséum National d'Histoire Naturelle
The French National Museum of Natural History, known in French as the ' (abbreviation MNHN), is the national natural history museum of France and a ' of higher education part of Sorbonne Universities. The main museum, with four galleries, is loc ...
(MNHN,
Paris
Paris () is the capital and most populous city of France, with an estimated population of 2,165,423 residents in 2019 in an area of more than 105 km² (41 sq mi), making it the 30th most densely populated city in the world in 2020. S ...
), and the anterior part of a left
maxilla
The maxilla (plural: ''maxillae'' ) in vertebrates is the upper fixed (not fixed in Neopterygii) bone of the jaw formed from the fusion of two maxillary bones. In humans, the upper jaw includes the hard palate in the front of the mouth. T ...
, described by Sauvage in 1882, was found through a Parisian
fossil dealer
The fossil trade is the purchase and sale of fossils. This is many times done illegally with stolen fossils, and many important scientific specimens are lost each year. The trade is lucrative, and many celebrities collect fossils.
The fossil t ...
in the late 20th century and purchased by Christian de Muison, a
paleontologist
Paleontology (), also spelled palaeontology or palæontology, is the scientific study of life that existed prior to, and sometimes including, the start of the Holocene epoch (roughly 11,700 years before present). It includes the study of fossi ...
at the MNHN.
The casts and the incomplete maxilla allowed for a reevaluation of ''Erectopus'' by