Dinodontosaurus

Dinodontosaurus
Temporal range: Mid-Late Triassic
~242–229 Ma
Mounted Dinodontosaurus tener skeleton
D. tener illustration
Scientific classification Edit this classification
Kingdom: Animalia
Phylum: Chordata
Clade: Synapsida
Clade: Therapsida
Clade: †Anomodontia
Clade: †Dicynodontia
Clade: †Kannemeyeriiformes
Genus: †Dinodontosaurus
Romer, 1943
Type species
†Dinodontosaurus oliveirai
Species
  • D. brevirostris Cox, 1968
  • D. isiyavamanda George et al., 2026
  • D. tener (Huene, 1935)
  • D. turpior (Huene, 1935) [nomen dubium]
Synonyms
Genus synonymy
Species synonymy
  • Synonyms of D. brevirostris:
    • Chanaria platyceps Cox, 1968
    • D. platygnathus Cox, 1968
  • Synonyms of D. tener:
    • Diodontosaurus pedroanum Tupí-Caldas, 1936
    • D. oliveirai Romer, 1943

Dinodontosaurus (meaning "terrible-toothed lizard") is a genus of dicynodont therapsid which lived in South America (Brazil and Argentina) and Southern Africa (Tanzania) from the Middle Triassic to the Upper Triassic. It was medium to large sized dicynodont with a skull up to 40 centimetres (16 in) long and had a beak corneum. At least three species belong to this genus: D. brevirostris, D. tener, and D. isiyavamanda. There is a fourth species that is a nomen dubium, D. turpior.

Taxonomy

Species

Phylogeny

Dinodontosaurus in a cladogram from Szczygielski & Sulej (2023):

Kannemeyeriiformes

Description

Life restoration of D. isiyavamanda by Gabriel Ugueto

Dinodontosaurus was a medium to larger sized dicynodont. It has a skull length of up to 40 centimetres (16 in). It possessed both tusks that were notably elongated and curved and beak corneum. Specimens of Dinodontosaurus tener has a high amount of morphological variability among known specimens. While some of this variation is partially due to taphonomic alterations to the skeletons, this variation is potentially due to intraspecific or even interspecific variation.

Paleoecology

Dinodontosaurus is one of the most common tetrapod taxon that lived during the Middle Triassic being more common in fossil layers from the Rio Grande do Sul and Santa Maria Supersequence.

Coprolites (fossilized dung) from the Chañares Formation that have been attributed to Dinodontosaurus suggest that it had a broad diet of low-lying plants.

References

  1. 1 2 Kammerer, C. F.; Ordoñez, M. D. (2021). "Dicynodonts (Therapsida: Anomodontia) of South America". Journal of South American Earth Sciences. 108 103171. Bibcode:2021JSAES.10803171K. doi:10.1016/j.jsames.2021.103171. S2CID 233565963.
  2. 1 2 George, Hady; Escobar, Juan A.; Moody, Edmund R.R.; Saanane, Charles B.; Day, Michael O.; Larkin, Nigel R. (2026-09-15). "Craniomandibular osteology of Dinodontosaurus isiyavamanda sp. nov. (Therapsida: Anomodontia) from the Manda Beds of Tanzania and new support for a younger age for the alleged oldest dinosaurs". Journal of Vertebrate Paleontology. doi:10.1080/02724634.2026.2692542. ISSN 0272-4634.
  3. 1 2 Paleobiology Database.
  4. ↑ "Giant prehistoric toilet unearthed", James Morgan, science reporter, BBC News, 28 November 2013
  5. ↑ Szczygielski, T.; Sulej, T. (2023). "Woznikella triradiata n. gen., n. sp. – a new kannemeyeriiform dicynodont from the Late Triassic of northern Pangea and the global distribution of Triassic dicynodonts". Comptes Rendus Palevol. 22 (16): 279–406. doi:10.5852/cr-palevol2023v22a16.
  6. 1 2 de Souza, Julia Lara Rodrigues; Da Silva, João Lucas; Neto, Voltaire D. P.; Machado, Arielli Fabrício; Escobar, Juan A.; Pinheiro, Felipe L. (2026). "Revisiting a long-overlooked skull: Implications for the distribution of Dinodontosaurus brevirostris (Kannemeyeriiformes) in the Brazilian Triassic". The Anatomical Record. 309 (7): 1749–1765. doi:10.1002/ar.70056. ISSN 1932-8494. PMC 13251750. PMID 41017743.
  7. ↑ Perez Loinaze, Valeria S.; Vera, Ezequiel I.; Fiorelli, Lucas E.; Desojo, Julia B. (2018). "Palaeobotany and palynology of coprolites from the Late Triassic Chañares Formation of Argentina: implications for vegetation provinces and the diet of dicynodonts". Palaeogeography, Palaeoclimatology, Palaeoecology. 502: 31–51. doi:10.1016/j.palaeo.2018.04.003. hdl:11336/81031.