Callovosaurus
{{Short description|Extinct genus of dinosaurs}}
{{Use dmy dates|date=April 2022}}
{{speciesbox
| fossil_range = Callovian
~{{Fossil range|164}}
| image = The Quarterly journal of the Geological Society of London (13936882312).jpg
| image_caption = Illustration of the holotype femur
| image_upright = 0.6
| genus = Callovosaurus
| parent_authority = Galton, 1980
| species = leedsi
| authority = Galton, 1980 (Lydekker, 1889)
| synonyms =
- Camptosaurus leedsi Lydekker, 1889
}}
Callovosaurus (meaning "Callovian lizard") is a genus of iguanodontian dinosaur known from most of a left thigh bone discovered in Middle Jurassic-age rocks of England. At times, it has been considered dubious or a valid genus of basal iguanodontian, perhaps a dryosaurid.
History and description
Callovosaurus is based on BMNH R1993, a nearly complete left thigh bone. This specimen was collected from the middle Callovian–age (Middle Jurassic) Peterborough Member (former Lower Oxford Clay) of the Oxford Clay Formation of Fletton, near Peterborough in Cambridgeshire, England. The bone is {{convert|28|cm|ft}} long, and is estimated to have belonged to an animal approximately {{cvt|2.5|m|ft}} in length. A partial shin bone from the same site or nearby, SMC J.46889, may also belong to Callovosaurus.{{cite book |last=Ruiz-Omeñaca |first=José Ignacio |author2=Pereda Suberbiola, Xabier |author3=Galton, Peter M. |year=2007 |chapter= Callovosaurus leedsi, the earliest dryosaurid dinosaur (Ornithischia: Euornithopoda) from the Middle Jurassic of England |editor= Carpenter, Kenneth |title= Horns and Beaks: Ceratopsian and Ornithopod Dinosaurs |publisher=Indiana University Press |location=Bloomington and Indianapolis |pages=3–16 |isbn=978-0-253-34817-3}}
The type species, C. leedsi, was first described by Richard Lydekker in 1889 as Camptosaurus leedsi, the specific name honouring collector Alfred Nicholson Leeds.{{cite journal |last=Lydekker |first=Richard |author-link=Richard Lydekker |year=1889 |title=On the remains and affinities of five genera of Mesozoic reptiles |journal=Quarterly Journal of the Geological Society of London |volume=45 |issue=1–4 |pages=41–59
| doi = 10.1144/GSL.JGS.1889.045.01-04.04 |s2cid=128586645 }} Aside from Charles W. Gilmore suggesting in 1909 that it was probably more closely related to Dryosaurus than to Camptosaurus,{{cite journal |last=Gilmore |first=Charles W. |year=1909 |title=Osteology of the Jurassic reptile Camptosaurus, with a revision of the genus, and description of two new species |journal=Proceedings of the United States National Museum |volume=36 |pages=197–332 |issue=1666 | doi=10.5479/si.00963801.36-1666.197|url=https://www.biodiversitylibrary.org/part/52542 }} Camptosaurus leedsi attracted little attention for decades until it was reviewed by Peter Galton. First noting its distinctiveness in a review of English hypsilophodontids,{{cite journal |last=Galton |first=Peter M. |author-link=Peter Galton |year=1975 |title=English hypsilophodontid dinosaurs (Reptilia:Ornithischia) |journal=Palaeontology |volume=18 |issue=4 |pages=741–752 |url=http://palaeontology.palass-pubs.org/pdf/Vol%2018/Pages%20741-752.pdf }} he then gave the species the new genus Callovosaurus in 1980, which he placed in Camptosauridae.{{cite journal |last=Galton |first=Peter M. |author-link=Peter Galton |year=1980 |title=European Jurassic ornithopod dinosaurs of the families Hypsilophodontidae and Camptosauridae |journal=Neues Jahrbuch für Geologie und Paläontologie, Abhandlungen |volume=160 |issue=1 |pages=73–95|doi=10.1127/njgpa/160/1980/73 }} While considered a dubious iguanodontian in several reviews, which refer to it as "Camptosaurus" leedsi,{{cite book |last=Norman |first= David B. |author2=Weishampel, David B. |editor=Weishampel, David B. |editor2=Dodson, Peter |editor3=Osmólska, Halszka |title=The Dinosauria |year=1990 |publisher=University of California Press |location=Berkeley |isbn=0-520-06727-4 |pages=510–533 |chapter=Iguanodontidae and related ornithopods}}{{cite book |last= Norman|first=David B. |editor= Weishampel, D.B. |editor2=Dodson, P. |editor3=Osmólska, H. |title=The Dinosauria |edition=2nd |year= 2004|publisher=University of California Press |location=Berkeley |isbn=0-520-24209-2 |pages=413–437 |chapter=Basal Iguanodontia}} Jose Ignacio Ruiz-Omeñaca and coauthors have proposed that Callovosaurus is a valid genus, and the oldest known dryosaurid.
Palaeoecology
Callovosaurus was found in the lower Oxford Clay, which has yielded a diverse reptile assemblage: ichthyosaurs, plesiosaurs, crocodyliforms, pterosaurs, sauropod dinosaurs, the stegosaurids Loricatosaurus and Lexovisaurus, and the armoured dinosaur Sarcolestes.{{cite journal |last=Maidment |first=Susannah C.R. |author2=Norman, David B. |author3=Barrett, Paul M. |author4= Upchurch, Paul |year=2008 |title=Systematics and phylogeny of Stegosauria (Dinosauria: Ornithischia) |journal=Journal of Systematic Palaeontology |doi=10.1017/S1477201908002459 |volume=6 |issue=4 |pages=367–407|bibcode=2008JSPal...6..367M |s2cid=85673680 }} These rocks were once thought to be somewhat younger, from the Oxfordian of the Late Jurassic, but they are now known to be middle Callovian in age.
The diet of Callovosaurus, like that of other iguanodontians, was plant material. It is one of the earliest known members of the iguanodontian lineage.{{cite book |editor=Palmer, D.|year=1999 |title= The Marshall Illustrated Encyclopedia of Dinosaurs and Prehistoric Animals|publisher= Marshall Editions|location=London|page= 142|isbn= 1-84028-152-9}}
References
{{Reflist}}
External links
- [https://paleobiodb.org/classic/checkTaxonInfo?taxon_no=38747 Callovosaurus] in The Paleobiology Database
{{Ornithopoda|O.}}
{{Taxonbar|from=Q1579204}}
Category:Fossil taxa described in 1980
Category:Taxa named by Peter Galton
Category:Oxford Clay Formation