Saturnalia (dinosaur)

Taxobox
name = "Saturnalia"
fossil_range = Late Triassic
regnum = Animalia
phylum = Chordata
classis = Sauropsida
superordo = Dinosauria
ordo = Saurischia
familia = Guaibasauridae
genus = "Saturnalia"
genus_authority= Langer "et al"., 1999
subdivision_ranks=Species
subdivision=
* "S. tupiniquim" Langer "et al.", 1999 (type)

"Saturnalia" is a genus of very early saurischian dinosaur, from the Carnian faunal stage of the late Triassic period (227.4 to 220.7 million years ago), making it one of the oldest true dinosaurs yet found. It may have been a primitive sauropodomorph, a group which includes the giant sauropods. It probably grew to about 1.5 meters (5 ft) long. The few known remains of this genus have many prosauropod features, yet lack other characteristics shared by all dinosaurs.

Classification

The primitive nature of "Saturnalia", combined with its mixture of sauropodomorph and theropod characteristics, has made it difficult to classify. Paleontologist Max Cardoso Langer and colleagues, in their 1999 description of the genus, assigned it to the Sauropodomorpha.Langer, M.C., Abdala, F., Richter, M., and Benton, M. (1999). "A sauropodomorph dinosaur from the Upper Triassic (Carnian) of southern Brazil." "Comptes Rendus de l'Académie des Sciences", 329: 511-;517.] However, in a 2003 paper, Langer noted that features of its skull and hand were more similar to the sister group of sauropodomorphs, the theropods, and that "Saturnalia" could at best be considered a member of the sauropodomorph "stem-lineage", rather than a true member of that group.Langer, M.C. (2003). "The pelvic and hind limb anatomy of the stem-sauropodomorph "Saturnalia tupiniquim" (Late Triassic, Brazil)." "PaleoBios", 23(2): September 15, 2003.]

Jose Bonaparte and colleagues, in a 2007 study, found "Saturnalia" to be very similar to the primitive saurischian "Guaibasaurus". Bonaparte placed the two in the same family, Guaibasauridae. Like Langer, Bonaparte found that these forms may have been primitive sauropodomorphs, or an assemblage of forms close to the common ancestor of the sauropodomorphs and theropods. Overall, Bonaparte found that both "Saturnalia" and "Guaibasaurus" were more theropod-like than prosauropod-like.Bonaparte, J.F., Brea, G., Schultz, C.L., and Martinelli, A.G. (2007). "A new specimen of "Guaibasaurus candelariensis" (basal Saurischia) from the Late Triassic Caturrita Formation of southern Brazil." "Historical Biology", 19(1): 73-82.]

Discovery and species

The holotype was discovered in mid-winter at Sanga da Alemoa, Rio Grande do Sul, in Brazil, and additional remains were discovered during the Roman winter solstice festival, Saturnalia; after which it was named in 1999, along with a Portuguese/Guarani word meaning "native". The partial skeleton and referred remains from two other specimens including a jaw and teeth have also been discovered.

References

ee also

*Paleorrota

External links

* [http://www.dinodata.org/index.php?option=com_content&task=view&id=7490&Itemid=67 "Saturnalia" at DinoData] .
* [http://www.palaeos.com/Vertebrates/Units/330Sauropodomorpha/330.100.html Vertebrates 330.100 Sauropodomorpha : Prosauropoda] , from Palæos. (technical)
* [http://www.users.qwest.net/~jstweet1/sauropodomorpha.htm Sauropodomorpha]
* [http://www.royalsul.com.br/paleo/galeria.asp Dinosaurs of Rio grande do Sul.]