''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 lo ...

which existed in

Argentina Argentina, officially the Argentine Republic, is a country in the southern half of South America. It covers an area of , making it the List of South American countries by area, second-largest country in South America after Brazil, the fourt ...

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 a ...

(

Carnian The Carnian (less commonly, Karnian) is the lowermost stage (stratigraphy), stage of the Upper Triassic series (stratigraphy), Series (or earliest age (geology), age of the Late Triassic Epoch (reference date), Epoch). It lasted from 237 to 227.3 ...

) period. It is from the Cancha de Bochas, Valle Pintado member of the Ischigualasto Formation. It was a small, bipedal

herbivore A herbivore is an animal anatomically and physiologically evolved to feed on plants, especially upon vascular tissues such as foliage, fruits or seeds, as the main component of its diet. These more broadly also encompass animals that eat ...

, about in length.

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: 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 of all kno ...

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

holotype A holotype (Latin: ''holotypus'') is a single physical example (or illustration) of an organism used when the species (or lower-ranked taxon) was formally described. It is either the single such physical example (or illustration) or one of s ...

, PVSJ 845, was found in the Cancha de Bochas Member of the Ischigualasto Formation, 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 Geological period, period, between 243 and 233.23 million years ago (mya), although the exact origin and timing of the #Evolutio ...

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 ( ; from Ancient Greek 'branch') 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 ...

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

clade In biology, a clade (), also known as a Monophyly, monophyletic group or natural group, is a group of organisms that is composed of a common ancestor and all of its descendants. Clades are the fundamental unit of cladistics, a modern approach t ...

basal sauropodomorphs, the

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

, together with '' Guaibasaurus'', the disputed '' Agnosphitys'', '' Panphagia'' and ''

Saturnalia Saturnalia is an Roman festivals, ancient Roman festival and holiday in honour of the List of Roman deities, god Saturn (mythology), Saturn, held on 17 December in the Julian calendar and later expanded with festivities until 19 December. By t ...

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

References

{{Portal bar, Dinosaurs Saturnaliidae Dinosaur genera Carnian dinosaurs Ischigualasto Formation Fossil taxa described in 2010 Dinosaurs of Argentina