Quilmesaurus
- Río Negro, Argentina (Allen Formation)
- Quilmesaurus curriei
Quilmesaurus is a dubious ( doubtful ) Genre theropod dinosaur from the Upper Cretaceous of Argentina. The first and only fund consists only of the right tibia and the lower end of the right femur and comes from the Allen Formation ( Campanian to Maastrichtian ). It is attributed to the Abelisauroidea, a group within the Ceratosauria, and was within this group likely to Abelisauridae. Quilmesaurus was scientifically described in 2001 by Rodolfo Coria with the only kind Quilmesaurus curriei.
Research History and naming
The Fund ( copy number MPCA - PV -100) was discovered in the late 1980s by an excavation team from the Universidad Nacional de Tucumán, headed by Jaime Powell. He comes from fluvial sandstones from the lower portion of the Allen lineup. It was the first discovered in this formation discovery of a theropod. The site ( Salitral Ojo de Agua ) is located south of the city of General Roca, in the Argentine province of Río Negro.
The name Quilmesaurus has the tribe of Quilmes. The second part of the species name, curriei, honors the paleontologist Philip Currie major Canadian.
Features
The body length of this animal was estimated from the reconstructed femur length to 6.3 to 8 feet. Compared with other Abelisauriden the leg bones are long and slender. The classification within the Abelisauridae is supported among others by the strong expression of mediodistalen ridge on the lower end of the femur. An unusual feature is the hook-shaped in side view Cnemialkamm, a prominent bony crest on the front of the upper end of the tibia.
Systematics and validity
Originally classified Rodolfo Coria (2001) Quilmesaurus as theropod with unknown relationships. Coria rule out an assignment to the Ceratosauria because the shin has no signs of mergers with the bones of the ankle, as is the case with other then-known representatives of the Ceratosauria. Today, a similar anatomy has been, however, also been observed in other Ceratosauria as Majungasaurus. Currently, the Fund within the Abelisauroidea is classified, various features have also to a position within the Abelisauridae. In the redescription of the fossil in 2007 Juárez Valieri and colleagues come to the conclusion that it is possibly due to Carnotaurinae, a subgroup of the Abelisauridae.
In a study published in 2007 redescription of the fossil Quilmesaurus is declared as a noun dubium, since no features could be identified by which this species can be distinguished from other genera ( autapomorphies ).