Open Paleo

Arcusaurus

Yates et al., 2011 AR-kyoo-SAWR-us

From Latin 'arcus' meaning 'rainbow', a reference to South Africa being known as the Rainbow Nation, combined with Greek 'sauros' meaning 'lizard'.

201.4–192.9 million years ago Hettangian–Sinemurian, Early Jurassic
Early Jurassic stages

Arcusaurus is an extinct genus of sauropodomorph dinosaur from the Early Jurassic (Pliensbachian stage) of South Africa. Arcusaurus was first named by Adam Yates, Matthew Bonnan and Johann Neveling in 2011 and the type species is Arcusaurus pereirabdalorum. The generic name is derived from Latin arcus, "rainbow", a reference to the Rainbow Nation. The specific epithet honors Lucille Pereira and Fernando Abdala who discovered the fossils.

Diagnosis

  1. Horizontal medial shelf projecting from dorsal margin of premaxillary body, offset caudally by a notch
  2. Base of caudomedial process of premaxilla expanded into a horizontal palatal shelf contacting its antimere
  3. Postorbital with parietal articulation surface borne on a dorsally projecting semilunate process
  4. Fine ridge on nasal extending from medial edge of prefrontal embayment to near center of bone
  5. Dentary with a single enlarged neurovascular foramen opening near the rostral tip of the lateral surface
  6. Distal caudal vertebra with dorsoventrally compressed centrum (cranial face 1.43 times wider than high)

Species

Arcusaurus pereirabdalorum Yates et al., 2011

Type species

Named for Lucille Pereira and Fernando Abdala, who discovered the fossils.

Holotype
BP/1/6235 , Evolutionary Studies Institute (formerly Bernard Price Institute for Palaeontological Research), University of the Witwatersrand
Material
Partial skull including nasal, postorbital, dentary, coronoid, maxillary teeth, and possibly a caudal vertebra
Horizon
upper Elliot Formation, Hettangian–Sinemurian, Early Jurassic , 201.4–192.9 million years ago
Locality
Sauropod Quarry, farm Spion Kop 932, Free State, South Africa

References

  1. Yates, A. M.; Bonnan, M. F.; Neveling, J. (2011). A new basal sauropodomorph dinosaur from the Early Jurassic of South Africa. Journal of Vertebrate Paleontology 31(3): 610-625. Informa UK Limited. doi:10.1080/02724634.2011.560626 yates2011a
  2. Jones, B. (2026). The Princeton Encyclopedia of Dinosaurs: Sauropods. Princeton University Press.

    Source of the body length estimate.

    jones2026b