Krzyzanowskisaurus

Taxobox
name = "Krzyzanowskisaurus"
fossil_range = Late Triassic
regnum = Animalia
phylum = Chordata
classis = Sauropsida
subclassis = Diapsida
unranked_ordo = Archosauria
unranked_familia = ?Crurotarsi
genus = "Krzyzanowskisaurus"
binomial = "Krzyzanowskisaurus hunti"
binomial_authority = (Heckert, 2002)

"Krzyzanowskisaurus" is the name given to a genus of archosaur from the Late Triassic. The generic name honours Stan Krzyżanowski. It is a tooth taxon, based on fossils only of teeth. These teeth have been found in the U.S. states of Arizona (including the type locality) and New Mexico. The original report described it as a "probable ornithischian". Heckert (2005) suggests that "Krzyzanowskisaurus" teeth have biostratigraphic utility as an index fossil of the St. Johnsian sub-lvf (land-vertebrate faunachron).

The type species, "Krzyzanowskisaurus hunti", was reevaluated by Heckert in 2005, after previously being described by him as "Revueltosaurus hunti" in 2002. The name was changed when it was discovered that the type species of "Revueltosaurus", "R. callenderi", was a pseudosuchian rather than an ornithischian dinosaur (Parker "et al". 2005). According to Heckert, "R." "hunti" displays an orithischian-like feature not present in "R. callenderi" (teeth possessing a cingulum), suggesting that it represents a new genus of early ornithischian. This was challenged by Irmis "et al". (2006), who found that the cingulum differed from that in true early ornithischians, and noted that some teeth had been found with skull bones and osteoderms that matched those of "Revueltosaurus". Thus, they found that it was not a dinosaur, and provisionally retained it in "Revueltosaurus"; it may once again be "R. hunti."

References

* Heckert, A.B., 2005. "Krzyzanowskisaurus", a new name for a probable ornithischian dinosaur from the Upper Triassic Chinle Group, Arizona and New Mexico, USA. "New Mexico Museum of Natural History and Science Bulletin" 29: 77-83.
* Irmis, R.B., Parker, W.G., Nesbitt, S.J., and Liu, J. (2006). Early ornithischian dinosaurs: the Triassic record. Historical Biology, 19(1):3-22.
* Parker, W. G., R. B. Irmis, S.N. Nesbitt, J. W. Martz & L. S. Browne. 2005. The pseudosuchian "Revueltosaurus callenderi" and its implications for the diversity of early ornithischian dinosaurs. "Proceedings of the Royal Society London" B272 (1566): 963–969.
* http://www.users.qwest.net/~jstweet1/dinosauromorpha.htm
* http://dml.cmnh.org/2005Nov/msg00284.html
* http://www.dinosaurier-web.de/galery/pages_k/krzyzanowskisaurus.html with picture