Riojasauridae

The Late Triassic is in the geologic timescale the third and final of three epochs of the Triassic period. The corresponding series is known as the Upper Triassic. In the past it was sometimes called the Keuper, after a German lithostratigraphic group that has a roughly corresponding age...

Animals are a major group of mostly multicellular, eukaryotic organisms of the kingdom Animalia or Metazoa. Their body plan eventually becomes fixed as they develop, although some undergo a process of metamorphosis later on in their life. Most animals are motile, meaning they can move spontaneously...

Chordates are animals which are either vertebrates or one of several closely related invertebrates. They are united by having, for at least some period of their life cycle, a notochord, a hollow dorsal nerve cord, pharyngeal slits, an endostyle, and a post-anal tail...

Reptiles, or members of the class Reptilia, are air-breathing, generally "cold-blooded" amniotes that generally have skin covered in scales or scutes. They are tetrapods and lay amniote eggs, whose embryos are surrounded by the amnion membrane...

Riojasauridae is a family of sauropod-like dinosaurs from the Upper Triassic. It is known primarily from the genera

Genus

In biology, a genus is a taxonomic unit used in the classification of living and fossil organisms. The term comes from Latin genus "descent, family, type, gender" , cognate with – genos, "race, stock, kin" ..In addition, genus is a taxonomic rank in the hierarchy In biology, a genus (plural:...

 Riojasaurus

Riojasaurus

Riojasaurus was a herbivorous prosauropod dinosaur named after La Rioja Province in Argentina where it was found by José Bonaparte. It lived during the Late Triassic and grew to about long. Riojasaurus is the only known Riojasaurid to live in South America.-Description:Riojasaurus had a heavy...

and Eucnemesaurus

Eucnemesaurus

Eucnemesaurus is a basal sauropodomorph dinosaur genus usually considered to be a synonym of Euskelosaurus. Recent study by Yates , however, indicates that it is valid and the same animal as putative "giant herrerasaurid" Aliwalia...

. Sites containing Riojauridae include the Lower Elliot Formation of Orange Free State

Orange Free State

The Republic of the Orange Free State was an independent Boer republic in southern Africa during the second half of the 19th century, and later a British colony and a province of the Union of South Africa. It is the historical precursor to the present-day Free State province...

, South Africa

South Africa

The Republic of South Africa is a country located at the southern tip of Africa, with a coastline on the Atlantic and Indian Oceans. To the north lie Namibia, Botswana and Zimbabwe, to the east are Mozambique and Swaziland, while Lesotho is an independent country surrounded by South Africa.Modern...

 (where fossils of Eucnemesaurus have been found), and Ischigualasto

Ischigualasto

Ischigualasto is a geological formation and a natural park associated with it in the province of San Juan, north-western Argentina, near the border with Chile...

, in La Rioja Province

La Rioja Province (Argentina)

La Rioja is a one of the provinces of Argentina and is located in the west of the country. Neighboring provinces are from the north clockwise Catamarca, Córdoba, San Luis and San Juan....

, Argentina

Argentina

Argentina, officially the Argentine Republic , is the second largest country in South America, constituted as a federation of 23 provinces and an autonomous city, Buenos Aires. It is the eighth largest country in the world by land area and the largest among Spanish-speaking nations, though Mexico,...

 ( where fossils of Riojasaurus have been recovered).
Basal sauropodomorph phylogeny simplified after Yates, 2007. This is only one of many proposed cladograms for basal sauropodomorphs.

External links

• Sauropodomorpha from Thescelosaurus!