Cardiodon

Taxobox|
name = "Cardiodon"
fossil_range = Middle Jurassic
regnum = Animalia
phylum = Chordata
classis = Sauropsida
superordo = Dinosauria
ordo = Saurischia
subordo = Sauropodomorpha
infraordo = Sauropoda
unranked_familia = ?Turiasauria
genus = "Cardiodon"
genus_authority = Owen, 1841
binomial = "Cardiodon rugulosus"
binomial_authority = Owen, 1844

"Cardiodon" (meaning "heart tooth", in reference to the shape) was a genus of sauropod dinosaur, based on a tooth from the late Bathonian-age Middle Jurassic Forest Marble Formation of Wiltshire, England. Historically, it is very obscure and usually referred to "Cetiosaurus", but recent analyses suggest that it is a distinct genus, and possibly related to "Turiasaurus".

History and Taxonomy

Richard Owen named the genus for a now-lost tooth found near Bradford-on-Avon, but did not assign it a species name at the time;Owen, R. (1841). Odontography, Part II. "Hippolyte Baillière." 655 p.] a few years later, he added the species name.Owen, R. (1844). Odontography, Part III. "Hippolyte Baillière." 655 p. ] Within a few decades, he and others were viewing it as a possible synonym of his most well-known sauropod genus, "Cetiosaurus".Phillips, J. (1871). "Geology of Oxford and the Valley of the Thames". Clarendon Press:Oxford, 529 p. ] Owen, R. (1875). Monographs of the fossil Reptilia of the Mesozoic formations (part III) (genera "Bothriospondylus", "Cetiosaurus", "Omosaurus"). Palaeontographical Society Monographs 29:15-93.] Richard Lydekker formalized this view in a roundabout way in 1890, by assigning "Cetiosaurus oxoniensis" to "Cardiodon" on the basis of teeth from Oxfordshire associated with a skeleton of "C. oxoniensis".Lydekker, R. (1890). Suborder Sauropoda. In: Lydekker, R. (ed.). "Catalogue of the Fossil Reptile and Amphibia of the British Museum (Natural History)." Part 1. Taylor and Francis:London, p. 131-152.] He also added a second tooth (BMNH R1527) from the Great Oolite near Cirencester, Gloucestershire. More typically, "Cardiodon" has been assigned to "Cetiosaurus", sometimes as a separate species.Steel, R. (1970). Part 14. Saurischia. "Handbuch der Paläoherpetologie/Encyclopedia of Paleoherpetology". Part 14. Gustav Fischer Verlag:Stuttgart, p. 1-87.]

In 2003, Paul Upchurch and John Martin, reviewing "Cetiosaurus", found that there is little evidence to assign the "C. oxoniensis" teeth to the skeleton, and the "C. oxoniensis" teeth differ from the "Cardiodon" teeth ("Cardiodon" teeth are convex facing the tongue); therefore, they supported "Cardiodon" being retained as its own genus.Upchurch, P.M., and Martin, J. (2003). The anatomy and taxonomy of "Cetiosaurus" (Saurischia, Sauropoda) from the Middle Jurassic of England. "Journal of Vertebrate Paleontology" 23(1):208-231.] Upchurch "et al." (2004) repeated this assessment, and found that though the teeth have no known autapomorphies, they are those of an eusauropod.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, p. 259-322. ISBN 0-520-24209-2] More recently, Royo-Torres "et al." (2006), in their description of "Turiasaurus", pointed out "Cardiodon" as a possible relative to their new, giant sauropod.Royo-Torres, R., Cobos, A., and Alcalá, L. (2006). A giant European dinosaur and a new sauropod clade. "Science" 314:1925-1927.]

Paleobiology

As a sauropod, "Cardiodon" would have been a large, quadrupedal herbivore, but because of the scanty remains, much more cannot be said.

References

External links

* [http://darrennaish.blogspot.com/2006/12/happy-christmas-from-gigantic-spanish.html Darren Naish's reaction to "Turiasaurus"]