''Bagualosaurus'' is a genus of

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 ...

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 ...

from the Candelária Sequence (Uppermost

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 othe ...

) of

Brazil Brazil, officially the Federative Republic of Brazil, is the largest country in South America. It is the world's List of countries and dependencies by area, fifth-largest country by area and the List of countries and dependencies by population ...

, dating to around 230 million years ago, in 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 227.3 ...

of the Late

Triassic The Triassic ( ; sometimes symbolized 🝈) is a geologic period and system which spans 50.5 million years from the end of the Permian Period 251.902 million years ago ( Mya), to the beginning of the Jurassic Period 201.4 Mya. The Triassic is t ...

. It includes one species, ''Bagualosaurus agudoensis''.

Discovery

In 2007, in a ravine at the outcrop of Janner, near Agudo in

Rio Grande do Sul Rio Grande do Sul (, ; ; "Great River of the South") is a Federative units of Brazil, state in the South Region, Brazil, southern region of Brazil. It is the Federative units of Brazil#List, fifth-most populous state and the List of Brazilian s ...

, a sauropodomorph skeleton was excavated. It was removed in a single block of stone. For five years it remained unprepared in the collection of the ''Laboratório de Paleovertebrados da Universidade Federal do Rio Grande do Sul'', curated by Cesar Leandro Schultz. In 2012, Flávio Augusto Pretto began to study the specimen. In 2018, Pretto, Max Cardoso Langer and Schultz named and described the

type species In International_Code_of_Zoological_Nomenclature, 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 spe ...

''Bagualosaurus agudoensis''. The generic name is derived from ''bagual'', "strongly built fellow" in the dialect of Rio Grande do Sul, in reference to the strong hindlimbs. The

specific name Specific name may refer to: * in Database management systems, a system-assigned name that is unique within a particular database In taxonomy, either of these two meanings, each with its own set of rules: * Specific name (botany), the two-part (bino ...

refers to the provenance from Agudo. 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 ...

, UFRGS-PV-1099-T, has been found in a layer of red mudstone of the Candelária sequence dating from the latest Carnian. It consists of a partial skeleton with skull. It contains the lower parts of the skull, the lower jaws, nine trunk vertebrae, three sacral vertebrae, two tail vertebrae, ribs, gastralia, chevrons, both ilia, the right pubis, both femora, both tibiae, both fibulae, and most of the left foot. The skeleton was partly articulated but has been damaged by erosion. It was found on its back with the hindlimbs pulled up, a rare position for archosaurian fossils.

Description

''Bagualosaurus'' was a modest-sized basal sauropodomorph, measuring approximately in length that, based on its teeth, was mostly

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 ...

. Features of its skull and dental structure are similar to ''

Pampadromaeus ''Pampadromaeus'' is an extinct genus of basal sauropodomorph dinosaurs known from the Late Triassic (Carnian) Santa Maria Formation of the Paraná Basin in Rio Grande do Sul, southern Brazil.Cabreira et al., 2011 Discovery ''Pampadromaeus'' ...

'', which comes from the same beds, and later

Norian The Norian is a division of the Triassic geological period, Period. It has the rank of an age (geology), age (geochronology) or stage (stratigraphy), stage (chronostratigraphy). It lasted from ~227.3 to Mya (unit), million years ago. It was prec ...

sauropodomorphs such as ''

Pantydraco ''Pantydraco'' (where "panty-" is short for Pant-y-ffynnon, signifying ''hollow of the spring/well'' in Welsh, referring to the quarry at Bonvilston in South Wales where it was found) is a genus of basal sauropodomorph dinosaur from the Late T ...

'', ''

Efraasia ''Efraasia'' (pronounced "E-FRAHS-ee-A") is a genus of basal (phylogenetics), basal sauropodomorph dinosaur. It was a herbivore which lived during the middle Norian stage of the Late Triassic, around 210 million years ago, in what is now Germ ...

'' and ''

Plateosaurus ''Plateosaurus'' (probably meaning "broad lizard", often mistranslated as "flat lizard") is a genus of plateosaurid dinosaur that lived during the Late Triassic period, around 214 to 204 million years ago, in what is now Central and Northern Eu ...

''. However, its post-cranial skeleton resembles earlier forms. Likewise, it is somewhat smaller than Norian sauropodomorphs, yet significantly larger (~45% based on femoral length) than other sauropodomorphs of the Carnian epoch, suggesting that it is transitional between the sauropodomorphs of its time and their later Norian descendants.

References

{{Taxonbar, from=Q54315693 Sauropodomorpha Dinosaur genera Campanian dinosaurs Santa Maria Formation Fossil taxa described in 2018 Dinosaurs of Brazil

Discovery

Description

See also

References