Ischyrosaurus

Taxobox
name = "Ischyrosaurus"
fossil_range = Upper Jurassic
regnum = Animalia
phylum = Chordata
classis = Sauropsida
superordo = Dinosauria
ordo = Saurischia
subordo = Sauropodomorpha
infraordo = Sauropoda
familia = unknown
genus = "Ischyrosaurus"
genus_authority = Hulke, 1874 ?"vide" Lydekker, 1888
species = "I. manseli"
species_authority = Hulke, 1874 ?"vide" Lydekker, 1888
binomial = "Ischyrosaurus manseli"
binomial_authority = Hulke, 1874 ?"vide" Lydekker, 1888

"Ischyrosaurus" (meaning "strong lizard", for its large humerus; name in quotation marks because it is preoccupied) was a genus of sauropod dinosaur from the Kimmeridgian-age Upper Jurassic Kimmeridge Clay of Dorset, Cambridgeshire, England. It is sometimes included with the Early Cretaceous-age wastebasket taxon "Pelorosaurus", although there is little evidence for this.

History and Taxonomy

"Ischyrosaurus" is based on a partial humerus (BMNH R41626) found in 1868.Hulke, J.W. (1869). Notes on a large saurian humerus from the Kimmeridge Clay of the Dorset Coast. "Proceedings of the Geological Society of London" June 23:386-389.] John Hulke described it briefly in 1869, then named it in 1874.Hulke, J.W. (1874). Note on a very large saurian limb-bone adapted for progression upon land, from the Kimmeridge Clay of Weymouth, Dorset. "Quarterly Journal of the Geological Society of London" 30:16-17.] The genus is preoccupied by a name Edward Drinker Cope coined in 1869 or 1870 (see for a discussion), but Cope's name was in use by 1871, so it predates Hulke's either way.

Like most sauropod remains from the Upper Jurassic-Lower Cretaceous of Europe, it became part of the "Pelorosaurus"-"Ornithopsis" taxonomic tangle, being referred first to "Ornithopsis" as "O. manseli",Lydekker, R. (1888). "Catalogue of the Fossil Reptilia and Amphibia in the British Museum (Natural History). Part I. Containing the Orders Ornithosauria, Crocodilia, Dinosauria, Squamata, Rhynchocephalia, and Proterosauria." British Museum (Natural History):London, 1-309.] then to "Pelorosaurus" as "P. manseli".von Huene, F. (1909). Skizze zu einer Systematik und Stammesgeschichte der Dinosaurier. "Centralblatt für Mineralogie, Geologie und Paläontologie" 1909:12-22. [German] ] Romer, A.S. (1956). "Osteology of the Reptiles". University of Chicago Press:Chicago 1-772. ISBN 0-89464985-X] Steel, R. (1970). Part 14. Saurischia. "Handbuch der Paläoherpetologie/Encyclopedia of Paleoherpetology". Part 14. Gustav Fischer Verlag:Stuttgart p. 1-87.]

Upchurch "et al.", in the most recent review (2004), lists it as a dubious sauropod of unknown affinities.Upchurch, P.M., Barrett, P.M., and Dodson, P. (2004). Sauropoda. In: Weishampel, D.B., Dodson, P., and Osmólska, H. (eds.). "The Dinosauria" (2nd edition). University of California Press:Berkeley 259-322. ISBN 0-520-24209-2] A new name is technically required, but because of the fractured taxonomy of Jurassic-Cretaceous European sauropods, researchers are waiting for better material.

Because "Ischyrosaurus" Cope, 1871, the unnecessary replacement name for "Ischyrotherium" Leidy, 1858, has been unused since 1899 and is therefore a "nomen oblitum", a petition will be submitted to the International Commission on Zoological Nomenclature to suppress "Ischyrosaurus" Cope, 1871 to conserve "Ischyrosaurus" Hulke, 1874 "vide" Lydekker, 1888 as the unpreoccupied scientific name.

Paleobiology

As a sauropod, it would have been a large quadrupedal herbivore.

References

External links

* [http://darrennaish.blogspot.com/2006/12/obscure-dinosaurs-of-kimmeridge-clay.htm Obscure Dinosaurs of the Kimmeridge Clay, by Darren Naish]
* [http://dml.cmnh.org/1995Oct/msg00135.html DML post on taxonomy of "Ischyrosaurus"]