''Valdosaurus'' ("

Weald The Weald () is an area of South East England between the parallel chalk escarpments of the North and the South Downs. It crosses the counties of Hampshire, Surrey, Sussex and Kent. It has three separate parts: the sandstone "High Weald" in the ...

Lizard") is a

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 ...

biped Bipedalism is a form of terrestrial locomotion where an organism moves by means of its two rear limbs or legs. An animal or machine that usually moves in a bipedal manner is known as a biped , meaning 'two feet' (from Latin ''bis'' 'double' a ...

herbivorous A herbivore is an animal anatomically and physiologically adapted to eating plant material, for example foliage or marine algae, for the main component of its diet. As a result of their plant diet, herbivorous animals typically have mouthpart ...

iguanodont Iguanodontia (the iguanodonts) is a clade of herbivorous dinosaurs that lived from the Middle Jurassic to Late Cretaceous. Some members include ''Camptosaurus'', ''Dryosaurus'', ''Iguanodon'', ''Tenontosaurus'', and the hadrosaurids or "duck-bil ...

ornithopod Ornithopoda () is a clade of ornithischian dinosaurs, called ornithopods (), that started out as small, bipedal running grazers and grew in size and numbers until they became one of the most successful groups of herbivores in the Cretaceous world ...

dinosaur Dinosaurs are a diverse group of reptiles of the clade Dinosauria. They first appeared during the Triassic period, between 243 and 233.23 million years ago (mya), although the exact origin and timing of the evolution of dinosaurs is t ...

found on the

Isle of Wight The Isle of Wight ( ) is a county in the English Channel, off the coast of Hampshire, from which it is separated by the Solent. It is the largest and second-most populous island of England. Referred to as 'The Island' by residents, the Isle of ...

and elsewhere in

England England is a country that is part of the United Kingdom. It shares land borders with Wales to its west and Scotland to its north. The Irish Sea lies northwest and the Celtic Sea to the southwest. It is separated from continental Europe b ...

Spain , image_flag = Bandera de España.svg , image_coat = Escudo de España (mazonado).svg , national_motto = ''Plus ultra'' (Latin)(English: "Further Beyond") , national_anthem = (English: "Royal March") , i ...

and possibly also

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 ...

. It lived during 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 ...

Discovery and naming

In the nineteenth century Reverend

William Darwin Fox The Reverend William Darwin Fox (23 April 1805 – 8 April 1880) was an English clergyman, naturalist, and a second cousin of Charles Darwin. Early life Fox was born in 1805 and initially raised at Thurleston Grange near Elvaston, Derbys ...

collected two small

thighbone The femur (; ), or thigh bone, is the proximal bone of the hindlimb in tetrapod vertebrates. The head of the femur articulates with the acetabulum in the pelvic bone forming the hip joint, while the distal part of the femur articulates with ...

s near Cowleaze Chine on the southwest coast of the Isle of Wight. In 1868 he incorrectly suggested these may have come from the same individual that had in 1848 been uncovered for

Gideon Mantell Gideon Algernon Mantell MRCS FRS (3 February 1790 – 10 November 1852) was a British obstetrician, geologist and palaeontologist. His attempts to reconstruct the structure and life of ''Iguanodon'' began the scientific study of dinosaurs: in ...

as a fossil of ''

Iguanodon ''Iguanodon'' ( ; meaning 'iguana-tooth'), named in 1825, is a genus of iguanodontian dinosaur. While many species have been classified in the genus ''Iguanodon'', dating from the late Jurassic Period to the early Cretaceous Period of Asia, Eu ...

'', and which in 1869 would be named as the new genus ''

Hypsilophodon ''Hypsilophodon'' (; meaning "''Hypsilophus''-tooth") is a neornithischian dinosaur genus from the Early Cretaceous period of England. It has traditionally been considered an early member of the group Ornithopoda, but recent research has put this ...

''. Regardless, both femora, made part of the collection of the

British Museum of Natural History The Natural History Museum in London is a museum that exhibits a vast range of specimens from various segments of natural history. It is one of three major museums on Exhibition Road in South Kensington, the others being the Science Museum an ...

as specimens BMNH R184 and BMNH R185, would be commonly referred to the latter genus. However, in 1975

Peter Galton Peter Malcolm Galton (born 14 March 1942 in London) is a British vertebrate paleontologist who has to date written or co-written about 190 papers in scientific journals or chapters in paleontology textbooks, especially on ornithischian and prosaur ...

named them as a new species of ''

Dryosaurus ''Dryosaurus'' ( , meaning 'tree lizard', Greek ' () meaning 'tree, oak' and () meaning 'lizard'; the name reflects the forested habitat, not a vague oak-leaf shape of its cheek teeth as is sometimes assumed) is a genus of an ornithopod dinosaur ...

'': ''Dryosaurus canaliculatus''. The specific name means "with a small channel" in

Latin Latin (, or , ) is a classical language belonging to the Italic branch of the Indo-European languages. Latin was originally a dialect spoken in the lower Tiber area (then known as Latium) around present-day Rome, but through the power of the ...

, referring to a distinct groove between the

condyle A condyle (;Entry "condyle"
in
In 1977 Galton named a new genus for them: ''Valdosaurus'', the name being derived from Latin ''Valdus'', " Wealden", a reference to the

Wealden Group The Wealden Group, occasionally also referred to as the Wealden Supergroup, is a group (a sequence of rock strata) in the lithostratigraphy of southern England. The Wealden group consists of paralic to continental (freshwater) facies sedimentary ...

. Its

type species In zoological nomenclature, a type species (''species typica'') is the species name with which the name of a genus or subgenus is considered to be permanently taxonomically associated, i.e., the species that contains the biological type specimen ...

, ''D. canaliculatus'', was thus renamed ''V. canaliculatus''.Galton, P.M., 1977. "The Upper Jurassic dinosaur ''Dryosaurus'' and a Laurasia-Gondwana connection in the Upper Jurassic", ''Nature'' 268(5617): 230-232 A second species, ''V. nigeriensis'', was described by Galton and

Philippe Taquet Philippe Taquet (b. April 25, 1940 Saint-Quentin, Aisne) is a French paleontologist who specializes in dinosaur systematics of finds primarily in northern Africa. He is a member of the French Academy of Sciences since November 30, 2004, president ...

from younger rocks from

Niger ) , official_languages = , languages_type = National languagesElrhazosaurus ''Elrhazosaurus'' (meaning " Elrhaz lizard") is a genus of basal iguanodontian dinosaur, known from isolated bones found in Early Cretaceous rocks of Niger. These bones were initially thought to belong to a species of the related dryosaurid ' ...

''. In 1998 William Blows inadvertently named another species, '' Valdosaurus dextrapoda'', by including this name in a fauna list, but this was an error, and the species has never been supported.Galton, P.M., 2009, "Notes on Neocomian (Late Cretaceous) ornithopod dinosaurs from England - ''Hypsilophodon'', ''Valdosaurus'', "Camptosaurus", "Iguanodon" - and referred specimens from Romania and elsewhere", ''Revue de Paléobiologie'' 28(1): 211-273 Lacking description, it is a ''

nomen nudum In taxonomy, a ''nomen nudum'' ('naked name'; plural ''nomina nuda'') is a designation which looks exactly like a scientific name of an organism, and may have originally been intended to be one, but it has not been published with an adequate descr ...

''.

Distribution and material

Having a close European relative of the American form ''Dryosaurus'' named led to most of the dryosaurid fossil material of Europe being referred to ''Valdosaurus''. ''Valdosaurus'' was seen as not only present in

(the

Wessex Formation The Wessex Formation is a fossil-rich English geological formation that dates from the Berriasian to Barremian stages (about 145–125 million years ago) of the Early Cretaceous. It forms part of the Wealden Group and underlies the younger Vecti ...

of the

and the

Hastings Beds The Wealden Group, occasionally also referred to as the Wealden Supergroup, is a group (a sequence of rock strata) in the lithostratigraphy of southern England. The Wealden group consists of paralic to continental (freshwater) facies sedimentary ...

West Sussex West Sussex is a county in South East England on the English Channel coast. The ceremonial county comprises the shire districts of Adur, Arun, Chichester, Horsham, and Mid Sussex, and the boroughs of Crawley and Worthing. Covering an ar ...

) but probably also in

. These rock units were deposited between the

Berriasian In the geological timescale, the Berriasian is an age/stage of the Early/Lower Cretaceous. It is the oldest subdivision in the entire Cretaceous. It has been taken to span the time between 145.0 ± 4.0 Ma and 139.8 ± 3.0 Ma (million years ago) ...

and

Barremian The Barremian is an age in the geologic timescale (or a chronostratigraphic stage) between 129.4 ± 1.5 Ma (million years ago) and 121.4 ± 1.0 Ma). It is a subdivision of the Early Cretaceous Epoch (or Lower Cretaceous Series). It is preceded ...

stages Stage or stages may refer to: Acting * Stage (theatre), a space for the performance of theatrical productions * Theatre, a branch of the performing arts, often referred to as "the stage" * ''The Stage'', a weekly British theatre newspaper * S ...

, between approximately 145 and 125 million years ago. ''V. canaliculatus'' would then be known from thigh bones, extensive additional

postcrania Postcrania (postcranium, adjective: postcranial) in zoology and vertebrate paleontology is all or part of the skeleton apart from the skull. Frequently, fossil remains, e.g. of dinosaurs or other extinct tetrapods, consist of partial or isolated sk ...

l elements, partial lower jaws, and teeth. In 2009 however, Galton critically reviewed the ''Valdosaurus'' material. He concluded that no fossils from outside England could be reliably referred to the genus. He thus gave ''V. nigeriensis'' its own genus: ''

Elrhazosaurus ''Elrhazosaurus'' (meaning " Elrhaz lizard") is a genus of basal iguanodontian dinosaur, known from isolated bones found in Early Cretaceous rocks of Niger. These bones were initially thought to belong to a species of the related dryosaurid ' ...

''. Even of many of the English specimens it was uncertain whether they belonged to ''Valdosaurus'', including all cranial elements and teeth. Some hindlimb and pelvis bones from the Upper

Weald Clay Formation Weald Clay or the Weald Clay Formation is a Lower Cretaceous sedimentary rock unit underlying areas of South East England, between the North and South Downs, in an area called the Weald Basin. It is the uppermost unit of the Wealden Group of ro ...

(late Barremian) were referable to ''V. canaliculatus''. Some material from the earlier Hastings Beds (

Valanginian In the geologic timescale, the Valanginian is an age or stage of the Early or Lower Cretaceous. It spans between 139.8 ± 3.0 Ma and 132.9 ± 2.0 Ma (million years ago). The Valanginian Stage succeeds the Berriasian Stage of the Lower Cretaceou ...

) were referred to a ''Valdosaurus'' sp. Galton established that

Richard Owen Sir Richard Owen (20 July 1804 – 18 December 1892) was an English biologist, comparative anatomist and paleontologist. Owen is generally considered to have been an outstanding naturalist with a remarkable gift for interpreting fossils. Owe ...

had in 1842 been the first to describe ''Valdosaurus'' thighbones, specimens BMB 004297-004300, assigning them to ''Iguanodon''. Galton emphasized that though the type femora were very small, fourteen centimetres long (which has led to estimates of a length of 1.2 metres and a weight of ten kilograms), these were from a juvenile individual and that an adult would have been a "medium-sized euornithopod", with some thighbones reaching a length of half a metre. In 2016, a new specimen of ''Valdosaurus'' was described. The specimen is the most complete yet found, which was found in articulation and includes a partial dorsal series, an almost complete tail, pelvic material, and both hind limbs. In life, the specimen would have been around long. Barrett, Paul. (2016). A new specimen of Valdosaurus canaliculatus (Ornithopoda: Dryosauridae) from the Lower Cretaceous of the Isle of Wight, England. Memoirs of Museum Victoria. 74. 29-48. 10.24199/j.mmv.2016.74.04.

Phylogeny

Galton assigned ''Valdosaurus'' to the Hypsilophodontidae, but this

paraphyletic In taxonomy (general), taxonomy, a group is paraphyletic if it consists of the group's most recent common ancestor, last common ancestor and most of its descendants, excluding a few Monophyly, monophyletic subgroups. The group is said to be pa ...

unnatural group has largely been abandoned. Today ''Valdosaurus'' is generally considered a member of the

Dryosauridae Dryosaurids were primitive iguanodonts. They are known from Middle Jurassic to Early Cretaceous rocks of Africa, Europe, and North America. Phylogeny Until recently many dryosaurids have been regarded as dubious ('' Callovosaurus'' and '' Kan ...

References

External links

''Valdosaurus'' at Dinosaur Isle

''Valdosaurus'' at National History Museum

''Valdosaurus'' at Dino Data
{{Taxonbar, from=Q1617586 Iguanodonts Barremian life Hauterivian life Valanginian life Early Cretaceous dinosaurs of Europe Cretaceous England Cretaceous Romania Cretaceous Spain Fossils of England Fossils of Romania Fossils of Spain Fossil taxa described in 1977 Taxa named by Peter Galton Ornithischian genera

Discovery and naming

Distribution and material

Phylogeny

See also

References

External links