| Rayososaurus | |
|---|---|
 | |
| Skeletal diagram | |
Scientific classification | |
| Kingdom: | Animalia |
| Phylum: | Chordata |
| Class: | Reptilia |
| Clade: | Dinosauria |
| Clade: | Saurischia |
| Clade: | †Sauropodomorpha |
| Clade: | †Sauropoda |
| Superfamily: | †Diplodocoidea |
| Family: | †Rebbachisauridae |
| Subfamily: | †Limaysaurinae |
| Genus: | †Rayososaurus Bonaparte, 1996 |
| Type species | |
| †Rayososaurus agrioensis Bonaparte, 1996 | |
Rayososaurus is an extinctgenus ofsauropoddinosaur in the familyRebbachisauridae.Rayososaurus was named by Argentinian paleontologistJosé Bonaparte in 1996. Itstype and only accepted species isRayososaurus agrioensis. The speciesLimaysaurus tessonei was at one point included inRayososaurus asRayososaurus tessonei.
The only known specimen ofRayososaurus agrioensis was discovered in 1991 by a team led byJosé F. Bonaparte, at a locality three kilometers south of Agrio del Medio inPicunches Department, Neuquén Province, Argentina. In 1996, Bonaparte described the remains as a new genus and species of sauropod,Rayososaurus agrioensis. Bonaparte believed that the strata the specimen was excavated from belonged to theRayoso Formation, and named the genus after it. The species name refers to theAgrio River, which the specimen was found near.[1] Bonaparte argued that the distinctive morphology of the scapula indicated thatRayososaurus was closely related toRebbachisaurus, which was considered adiplodocid at the time, and suggested that the two probably represent a previously-unrecognized clade of sauropods distinct from diplodocids. The following year, Bonaparte proposed the familyRebbachisauridae to encompassRayososaurus andRebbachisaurus.[2] Efforts undertaken in 2008 and 2009 re-located the original locality and determined that the specimen actually came from the upper layers of theCandeleros Formation.[3]
In 1998, Jeffrey Wilson and Paul Sereno proposed assigningRebbachisaurus tessonei toRayososaurus.[4] In 2004, Salgado and colleagues rejected this assignment and proposed the new genusLimaysaurus forR. tessonei, which is now known asLimaysaurus tessonei.[5]
Theholotype and only known specimen ofRayososaurus agrioensis, MACN-N 41, consists of two partialscapulae, most of the leftfemur, and the proximal half of the leftfibula.[3] TheCandeleros Formation, where the specimen was found, dates to theCenomanian age of theLate Cretaceous.[3]
Specimens from Brazil were assigned toRayososaurus in 2004,[6] but this was based on the now-rejected inclusion ofLimaysaurus tessonei inRayososaurus, so the specimens would better be referred toLimaysaurus, although they might actually be fragmentary remains ofAmazonsaurus.[3]
Rayososaurus has been considered a medium-sized sauropod,[7] with a body mass estimated at 9,353 kg.[8]Like other rebbachisaurids,Rayososaurus had a racquet-shaped scapula.[3]
