''Dinodontosaurus'' (meaning "terrible-toothed lizard") is a

genus Genus (; : genera ) is a taxonomic rank above species and below family (taxonomy), family as used in the biological classification of extant taxon, living and fossil organisms as well as Virus classification#ICTV classification, viruses. In bino ...

dicynodont Dicynodontia is an extinct clade of anomodonts, an extinct type of non-mammalian therapsid. Dicynodonts were herbivores that typically bore a pair of tusks, hence their name, which means 'two dog tooth'. Members of the group possessed a horny, t ...

therapsid. It was medium to large dicynodont of the

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 ...

(with skull up to long) and had a beak corneum. It lived in the

Middle Triassic In the geologic timescale, the Middle Triassic is the second of three epoch (geology), epochs of the Triassic period (geology), period or the middle of three series (stratigraphy), series in which the Triassic system (stratigraphy), system is di ...

but disappeared in the

Upper 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. T ...

Species

* ''Dinodontosaurus tener'' is the most common species of

that existed in the

, and more common in the fossil layers that age 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 ...

, in Rota Paleontológica. They are found mainly in the

Paleontological Site Chiniquá The Palaeontological Site Chiniquá is located in the Brazilian municipality of São Pedro do Sul, Rio Grande do Sul, along highway BR-287, about 70 kilometers west of the city of Santa Maria. The site occupies an area of about 250 hectares and ...

in São Pedro do Sul and Candelária, where a group of ten pups were found together, demonstrating that these animals had strategies for coexistence in a group and caring for their offspring. ''Diodontosaurus pedroanum'' Tupi-Caldas, 1936 and ''Dinodontosaurus oliveirai'',

Romer Romer, Römer, Roemer, or similar may refer to: * Romer (surname), includes a list of people with the name * Romer (tool), a cartographic device also known as a reference card * Rømer scale, a disused temperature scale named after Ole Rømer * ...

1943 are synonyms. * ''Dinodontosaurus brevirostris'' is known from skeleton remains and a

coprolite A coprolite (also known as a coprolith) is fossilized feces. Coprolites are classified as trace fossils as opposed to body fossils, as they give evidence for the animal's behaviour (in this case, diet) rather than morphology. The name ...

animal latrine Animal latrines (latrine areas, animal toilets, defecation sites) are places where wildlife animals habitually defecate and urinate. Many kinds of animals are highly specific in this respect and have stereotyped routines, including approach and d ...

"Giant prehistoric toilet unearthed"
James Morgan, science reporter, ''

BBC News BBC News is an operational business division of the British Broadcasting Corporation (BBC) responsible for the gathering and broadcasting of news and current affairs in the UK and around the world. The department is the world's largest broad ...

'', 28 November 2013 found in Argentina. ''Chanaria platyceps'' Cox, 1968 and ''Dinodontosaurus platygnathus'' are synonyms.

Phylogeny

''Dinodontosaurus'' in a

cladogram A cladogram (from Greek language, Greek ''clados'' "branch" and ''gramma'' "character") is a diagram used in cladistics to show relations among organisms. A cladogram is not, however, an Phylogenetic tree, evolutionary tree because it does not s ...

from Szczygielski & Sulej (2023):

Gallery

File:Dinodontosaurus skull.jpg, Skull (side) File:Dinodontosaurus skull 1.jpg, Skull (front) File:Dinodontosaurus museu2x.jpg, ''D. tener'' juveniles

References

{{Taxonbar, from=Q134272 Anomodont genera Kannemeyeriiformes Middle Triassic synapsids of South America Middle Triassic first appearances Late Triassic extinctions Late Triassic synapsids of South America Triassic Argentina Fossils of Argentina Paraná Basin Santa Maria Formation Triassic Brazil Fossils of Brazil Fossil taxa described in 1943 Taxa named by Alfred Romer