''Chromogisaurus'' is an extinct genus of saturnaliid

sauropodomorph Sauropodomorpha ( ; from Greek, meaning "lizard-footed forms") is an extinct clade of long-necked, herbivorous, saurischian dinosaurs that includes the sauropods and their ancestral relatives. Sauropods generally grew to very large sizes, had l ...

which existed in

Argentina Argentina (), officially the Argentine Republic ( es, link=no, República Argentina), is a country in the southern half of South America. Argentina covers an area of , making it the second-largest country in South America after Brazil, t ...

during the

Late Triassic The Late Triassic is the third and final epoch (geology), epoch of the Triassic geologic time scale, Period in the geologic time scale, spanning the time between annum, Ma and Ma (million years ago). It is preceded by the Middle Triassic Epoch ...

(

Carnian The Carnian (less commonly, Karnian) is the lowermost stage of the Upper Triassic Series (or earliest age of the Late Triassic Epoch). It lasted from 237 to 227 million years ago (Ma). The Carnian is preceded by the Ladinian and is followe ...

) period. It is from the Cancha de Bochas, Valle Pintado member of the

Ischigualasto Formation The Ischigualasto Formation is a Late Triassic fossiliferous formation and Lagerstätte in the Ischigualasto-Villa Unión Basin of the southwestern La Rioja Province and northeastern San Juan Province in northwestern Argentina. The formation d ...

. It was a

herbivore A herbivore is an animal anatomically and physiologically adapted to eating plant material, for example foliage or marine algae, for the main component of its diet. As a result of their plant diet, herbivorous animals typically have mouthp ...

about in length, and was optionally quadrupedal.

Description

''Chromogisaurus'' was first named by Martín Daniel Ezcurra in 2010, and the type species is ''Chromogisaurus novasi''. The generic name is derived from

Greek Greek may refer to: Greece Anything of, from, or related to Greece, a country in Southern Europe: *Greeks, an ethnic group. *Greek language, a branch of the Indo-European language family. **Proto-Greek language, the assumed last common ancestor ...

''chroma'', "colour", and ''gè'', "earth", a reference to the Valle Pintado, the "Painted Valley". The specific name honours

Fernando Emilio Novas Fernando Emilio Novas (born 1960) is an Argentine paleontologist working for the Comparative Anatomy Department of the Bernardino Rivadavia Natural Sciences Museum in Buenos Aires, Argentina.

. The

holotype A holotype is a single physical example (or illustration) of an organism, known to have been used when the species (or lower-ranked taxon) was formally described. It is either the single such physical example (or illustration) or one of seve ...

, PVSJ 845, was found in the Cancha de Bochas Member of the

, dating to the

. This makes ''Chromogisaurus'' one of the oldest known

dinosaur Dinosaurs are a diverse group of reptiles of the clade Dinosauria. They first appeared during the Triassic period, between 243 and 233.23 million years ago (mya), although the exact origin and timing of the evolution of dinosaurs is t ...

s. The specimen consists of a partial skeleton lacking the skull, with elements of the front and hind limbs, as well as the pelvis and two caudal vertebrae. A

cladistic Cladistics (; ) is an approach to biological classification in which organisms are categorized in groups (" clades") based on hypotheses of most recent common ancestry. The evidence for hypothesized relationships is typically shared derived ch ...

analysis by Ezcurra indicated that ''Chromogisaurus'' was a member of a clade basal

sauropodomorphs Sauropodomorpha ( ; from Greek, meaning "lizard-footed forms") is an extinct clade of long-necked, herbivorous, saurischian dinosaurs that includes the sauropods and their ancestral relatives. Sauropods generally grew to very large sizes, had l ...

, the

Guaibasauridae Guaibasauridae is a family of basal sauropodomorph dinosaurs, known from fossil remains of late Triassic period formations in Brazil and Argentina. Classification The exact makeup and classification of the Guaibasauridae remain uncertain. The ...

, together with '' Guaibasaurus'', the disputed ''

Agnosphitys ''Agnosphitys'' (; "unknown begetter"; sometimes mistakenly called ''Agnostiphys'' or ''Agnosphytis'') is a genus of dinosauriform that lived during the Late Triassic. It contains only one species, the type species ''A. cromhallensis''. Its rema ...

'', '' Panphagia'' and ''

Saturnalia Saturnalia is an ancient Roman festival and holiday in honour of the god Saturn, held on 17 December of the Julian calendar and later expanded with festivities through to 23 December. The holiday was celebrated with a sacrifice at the Temple o ...

''. Within Guaibasauridae, it forms a smaller clade with its sister taxon ''Saturnalia'', the

Saturnaliinae Saturnaliidae is a family of basal sauropodomorph dinosaurs found in Brazil, Argentina and possibly Zimbabwe. It is not to be confused with Saturnalidae, a family of radiolarian protists. Classification In 2010, Martin Ezcurra defined the subfam ...

References

Sauropodomorphs Dinosaur genera Carnian genera Late Triassic dinosaurs of South America Fossils of Argentina Triassic Argentina Ischigualasto Formation Fossil taxa described in 2010 {{Sauropodomorph-stub