''Saturnalia'' is an extinct

genus Genus ( plural genera ) is a taxonomic rank used in the biological classification of living and fossil organisms as well as viruses. In the hierarchy of biological classification, genus comes above species and below family. In binomial nom ...

of basal

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 lon ...

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 ...

known from the

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

Santa Maria Formation The Santa Maria Formation is a sedimentary rock formation found in Rio Grande do Sul, Brazil. It is primarily Carnian in age (Late Triassic), and is notable for its fossils of cynodonts, "rauisuchian" pseudosuchians, and early dinosaurs and other ...

of Rio Grande do Sul, southern Brazil and possibly the

Pebbly Arkose Formation The Pebbly Arkose Formation is a Late Triassic geologic formation found in southern Africa. Geology Description The formation comprises mainly coarse, arkosic sandstones. Extent The Pebbly Arkose Formation is found in Botswana, Zambia and ...

Zimbabwe Zimbabwe (), officially the Republic of Zimbabwe, is a landlocked country located in Southeast Africa, between the Zambezi and Limpopo Rivers, bordered by South Africa to the south, Botswana to the south-west, Zambia to the north, and ...

Discovery and naming

''Saturnalia'' was originally named on the basis of three partial skeletons. 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 sever ...

, MCP 3844-PV, a well-preserved semi-

articulated An articulated vehicle is a vehicle which has a permanent or semi-permanent pivot joint in its construction, allowing it to turn more sharply. There are many kinds, from heavy equipment to buses, trams and trains. Steam locomotives were sometim ...

postcrania Postcrania (postcranium, adjective: postcranial) in zoology and vertebrate paleontology is all or part of the skeleton apart from the skull. Frequently, fossil remains, e.g. of dinosaurs or other extinct tetrapods, consist of partial or isolated sk ...

l skeleton, was discovered in mid-summer at Sanga da Alemoa, Rio Grande do Sul, in

Brazil Brazil ( pt, Brasil; ), officially the Federative Republic of Brazil (Portuguese: ), is the largest country in both South America and Latin America. At and with over 217 million people, Brazil is the world's fifth-largest country by area ...

, in the

geopark A geopark is a protected area with internationally significant geology within which sustainable development is sought and which includes tourism, conservation, education and research concerning not just geology but other relevant sciences. In 2 ...

of Paleorrota. The two paratypes are MCP 3845-PV, partial skeleton including natural cast of partial

mandible In anatomy, the mandible, lower jaw or jawbone is the largest, strongest and lowest bone in the human facial skeleton. It forms the lower jaw and holds the lower teeth in place. The mandible sits beneath the maxilla. It is the only movable bone ...

with

teeth A tooth ( : teeth) is a hard, calcified structure found in the jaws (or mouths) of many vertebrates and used to break down food. Some animals, particularly carnivores and omnivores, also use teeth to help with capturing or wounding prey, t ...

and some postcranial remains, and MCP 3846-PV, partial skeleton including postcranial remains. All specimens were collected in the "Wald-Sanga" (also known as "Sanga do Mato") locality from the Alemoa Member of the

(Rosário do Sul Group), dating to the

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 m ...

faunal stage In chronostratigraphy, a stage is a succession of rock strata laid down in a single age on the geologic timescale, which usually represents millions of years of deposition. A given stage of rock and the corresponding age of time will by convent ...

of the early

, about 228

million years ago The abbreviation Myr, "million years", is a unit of a quantity of (i.e. ) years, or 31.556926 teraseconds. Usage Myr (million years) is in common use in fields such as Earth science and cosmology. Myr is also used with Mya (million years ago) ...

. A partial

femur The femur (; ), or thigh bone, is the proximal bone of the hindlimb in tetrapod vertebrates. The head of the femur articulates with the acetabulum in the pelvic bone forming the hip joint, while the distal part of the femur articulates wit ...

from the Carnian

has been speculated to belong to the genus. It is one of the oldest true dinosaurs yet found. It probably grew to about 1.5 meters (5 ft) long and . A U→Pb (

Uranium Uranium is a chemical element with the symbol U and atomic number 92. It is a silvery-grey metal in the actinide series of the periodic table. A uranium atom has 92 protons and 92 electrons, of which 6 are valence electrons. Uranium is weak ...

decay) dating found that the Santa Maria Formation dated around 233.23 million years ago, putting it 1.5 million years older than 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 ...

, and making the two formations approximately equal as the earliest dinosaur localities. ''Saturnalia'' was first named by Max C. Langer, Fernando Abdala, Martha Richter, Michael J. Benton in

1999 File:1999 Events Collage.png, From left, clockwise: The funeral procession of King Hussein of Jordan in Amman; the 1999 İzmit earthquake kills over 17,000 people in Turkey; the Columbine High School massacre, one of the first major school shoot ...

and the

type species In zoological nomenclature, a type species (''species typica'') is the species name with which the name of a genus or subgenus is considered to be permanently taxonomically associated, i.e., the species that contains the biological type specime ...

is ''Saturnalia tupiniquim''. The generic name is derived from ''Saturnalia'',

Latin Latin (, or , ) is a classical language belonging to the Italic branch of the Indo-European languages. Latin was originally a dialect spoken in the lower Tiber area (then known as Latium) around present-day Rome, but through the power of the ...

for "Carnival", in reference to the discovery of the paratypes during the feasting period. The specific name is derived from

Portuguese Portuguese may refer to: * anything of, from, or related to the country and nation of Portugal ** Portuguese cuisine, traditional foods ** Portuguese language, a Romance language *** Portuguese dialects, variants of the Portuguese language ** Portu ...

and Guarani word meaning ''native''.

Classification

The primitive nature of ''Saturnalia'', combined with its mixture of sauropodomorph and

theropod Theropoda (; ), whose members are known as theropods, is a dinosaur clade that is characterized by hollow bones and three toes and claws on each limb. Theropods are generally classed as a group of saurischian dinosaurs. They were ancestrally c ...

characteristics, has made it difficult to classify.

Paleontologist Paleontology (), also spelled palaeontology or palæontology, is the scientific study of life that existed prior to, and sometimes including, the start of the Holocene epoch (roughly 11,700 years before present). It includes the study of fossi ...

Max Cardoso Langer and colleagues, in their 1999 description of the genus, assigned it to the Sauropodomorpha.Langer, M.C., Abdala, F., Richter, M., and Benton, M. (1999).
A sauropodomorph dinosaur from the Upper Triassic (Carnian) of southern Brazil.
''Comptes Rendus de l'Académie des Sciences'', 329: 511-;517. However, in a 2003 paper, Langer noted that features of its skull and hand were more similar to the

s, and that ''Saturnalia'' could at best be considered a member of the sauropodomorph "stem-lineage", rather than a true member of that group.Langer, M.C. (2003)
"The pelvic and hind limb anatomy of the stem-sauropodomorph ''Saturnalia tupiniquim'' (Late Triassic, Brazil)"
''PaleoBios'', 23(2): September 15, 2003.

José Bonaparte José Fernando Bonaparte (14 June 1928 – 18 February 2020) was an Argentine paleontologist who discovered a plethora of South American dinosaurs and mentored a new generation of Argentine paleontologists . One of the best-known Argentine paleo ...

and colleagues, in a 2007 study, found ''Saturnalia'' to be very similar to the primitive saurischian ''

Guaibasaurus ''Guaibasaurus'' is an extinct genus of basal saurischian dinosaur known from the Late Triassic Caturrita Formation of Rio Grande do Sul, southern Brazil. Most analyses recover it as a sauropodomorph, although there are some suggestions that it ...

''. Bonaparte placed the two in the same

family Family (from la, familia) is a group of people related either by consanguinity (by recognized birth) or affinity (by marriage or other relationship). The purpose of the family is to maintain the well-being of its members and of society. Idea ...

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 ...

. Like Langer, Bonaparte found that these forms may have been primitive sauropodomorphs, or an assemblage of forms close to the common ancestor of the sauropodomorphs and theropods. Overall, Bonaparte found that both ''Saturnalia'' and ''Guaibasaurus'' were more theropod-like than prosauropod-like. However, all more recent

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 char ...

analyses found it to be a very basal sauropodomorph, possibly guaibasaurid, as the family was found to nest in a basal position within Sauropodomorpha.

References

External links

* *
Dinosaurs of Rio grande do Sul
{{Taxonbar, from=Q878443 Sauropodomorphs Late Triassic dinosaurs of Africa Fossils of Zimbabwe Late Triassic dinosaurs of South America Late Triassic sauropodomorphs Sauropodomorphs of Africa Sauropodomorphs of South America Triassic Brazil Fossils of Brazil Paleontology in Rio Grande do Sul Fossil taxa described in 1999

tupiniquim Tupiniquim (also Tupinã-ki, Topinaquis, Tupinaquis, Tupinanquins, Tupiniquins) are an indigenous people of Brazil, who now live in three indigenous territories (''Terras Indígenas'' in Portuguese). The indigenous territories (Caieiras Velha ...