Mantellisaurus
Encyclopedia
Mantellisaurus is a genus
of dinosaur
formerly known as Iguanodon
atherfieldensis. The new genus was erected by Gregory Paul in 2007. According to Paul, it is more lightly built than Iguanodon and more closely related to Ouranosaurus
, making Iguanodon in its traditional sense paraphyletic. It is known from many complete and almost complete skeletons. The genus name honours Gideon Mantell
, the discoverer of Iguanodon. Mantellisaurus lived during the Early Cretaceous
in what is now England
.
Compared to Iguanodon bernissartensis, Mantellisaurus was smaller, estimated at 0.75 tons
in weight. Its forelimbs were proportionally shorter than those of I. bernissartensis. In Mantellisaurus the forelimbs were about half the length of the hindlimbs whereas they were about 70 percent the length of the hindlimbs in I. bernissartensis. Due to the short length of its forelimbs and the shortness of its body, Paul proposed that it was primarily bipedal, only going on all fours when standing still or moving slowly.
The type fossil was originally discovered by Reginald Walter Hooley in 1914 in the upper Vectis Formation
of southern England and reported upon in 1917. He posthumously named it Iguanodon atherfieldensis in 1925. Atherfield is the name of a village on the southwest shore of the Isle of Wight
where the fossil was found. Heterosaurus, Sphenospondylus, and Vectisaurus may or may not be synonyms of Mantellisaurus, because Paul (2007) did not address the status of each of these names. Each of these taxa
were included as synonyms of I. atherfieldensis (as it was then known) in the 2004 review of Iguanodontia in The Dinosauria (2nd edition). Other possible synonyms include Dollodon
and Proplanicoxa
.
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 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...
formerly known 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...
atherfieldensis. The new genus was erected by Gregory Paul in 2007. According to Paul, it is more lightly built than Iguanodon and more closely related to Ouranosaurus
Ouranosaurus
Ouranosaurus is an unusual genus of herbivorous iguanodont dinosaur that lived during the early Cretaceous about 110 million years ago in what is now Africa. Ouranosaurus measured about seven to eight meters long...
, making Iguanodon in its traditional sense paraphyletic. It is known from many complete and almost complete skeletons. The genus name honours Gideon Mantell
Gideon Mantell
Gideon Algernon Mantell MRCS FRS was an English obstetrician, geologist and palaeontologist...
, the discoverer of Iguanodon. Mantellisaurus lived during the Early Cretaceous
Early Cretaceous
The Early Cretaceous or the Lower Cretaceous , is the earlier or lower of the two major divisions of the Cretaceous...
in what is now England
England
England is a country that is part of the United Kingdom. It shares land borders with Scotland to the north and Wales to the west; the Irish Sea is to the north west, the Celtic Sea to the south west, with the North Sea to the east and the English Channel to the south separating it from continental...
.
Compared to Iguanodon bernissartensis, Mantellisaurus was smaller, estimated at 0.75 tons
Short ton
The short ton is a unit of mass equal to . In the United States it is often called simply ton without distinguishing it from the metric ton or the long ton ; rather, the other two are specifically noted. There are, however, some U.S...
in weight. Its forelimbs were proportionally shorter than those of I. bernissartensis. In Mantellisaurus the forelimbs were about half the length of the hindlimbs whereas they were about 70 percent the length of the hindlimbs in I. bernissartensis. Due to the short length of its forelimbs and the shortness of its body, Paul proposed that it was primarily bipedal, only going on all fours when standing still or moving slowly.
The type fossil was originally discovered by Reginald Walter Hooley in 1914 in the upper Vectis Formation
Vectis Formation
The Vectis Formation is a geological formation on the Isle of Wight, England whose strata date back to the Early Cretaceous . The Vectis Formation is composed of three geological members: the Shepherds Chine member, the Barnes High Sandstone member, and the Cowleaze Chine member...
of southern England and reported upon in 1917. He posthumously named it Iguanodon atherfieldensis in 1925. Atherfield is the name of a village on the southwest shore of the Isle of Wight
Isle of Wight
The Isle of Wight is a county and the largest island of England, located in the English Channel, on average about 2–4 miles off the south coast of the county of Hampshire, separated from the mainland by a strait called the Solent...
where the fossil was found. Heterosaurus, Sphenospondylus, and Vectisaurus may or may not be synonyms of Mantellisaurus, because Paul (2007) did not address the status of each of these names. Each of these taxa
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...
were included as synonyms of I. atherfieldensis (as it was then known) in the 2004 review of Iguanodontia in The Dinosauria (2nd edition). Other possible synonyms include Dollodon
Dollodon
Dollodon is a genus of ornithopod dinosaur that lived in the Barremian and possibly the early Aptian ages of the Early Cretaceous Period of Europe. Its remains are known from Belgium , England and possibly Germany...
and Proplanicoxa
Proplanicoxa
Proplanicoxa is a genus of iguanodont which existed in what is now England during the Early Cretaceous period ....
.
Synonyms
- Iguanodon atherfieldensis Hooley, 1925
- ?Cetiosaurus brachyurus Owen, 1842
- ?Heterosaurus neocombiensis Cornuel, 1850
- ?Sphenospondylus gracilis Lydekker, 1888
- ?Vectisaurus valdensis Hulke, 1879