Open Paleo

Geranosaurus

Broom, 1911 juh-RAN-o-SOR-us Nomen dubium

From Ancient Greek 'geranos' meaning 'crane' and Greek 'sauros' meaning 'lizard', giving 'crane lizard'; the name refers to the bird-like limb bones, while the specific name atavus is Latin for 'ancestor', referencing its position as an early ornithischian.

199.5–184.2 million years ago Sinemurian–Pliensbachian, Early Jurassic
Early Jurassic stages

Geranosaurus is a genus of heterodontosaurid ornithischian dinosaur that lived during the Early Jurassic, between 191.1 and 187.5 million years ago. It is known from a single species, G. atavus, that was named in 1911 by Robert Broom for partial jaws found during road-cutting in South Africa. The genus name is likely derived from the word for "crane" in reference to the bird-like limb bones, while the species name means "ancestor" likely in reference to its position as an early ornithischian. The limited material and poor preservation of Geranosaurus have rendered it difficult to diagnose, with authors accepting it as a dubious name though differentiable from its relative Heterodontosaurus, the only other heterodontosaurid known from the Clarens Formation.

Under dispute

Geranosaurus is a nomen dubium based on fragmentary jaw material from the Early Jurassic of South Africa; it shows heterodontosaurid features, but they are not diagnosable (Norman and colleagues, 2011), and Sereno (2012) judges them inadequate for taxonomic recognition.

Species

Geranosaurus atavus Broom, 1911 Nomen dubium

Type species

From Latin 'atavus' meaning 'ancestor', likely referencing its position as one of the earliest known ornithischian dinosaurs.

Holotype
SAM-PK-1871 , Iziko South African Museum
Material
Partial lower jaws with teeth
Horizon
lower Clarens Formation, Sinemurian–Pliensbachian, Early Jurassic , 199.5–184.2 million years ago
Locality
road-cutting near the summit of Barkly Pass, Farm Tulloch, Elliot, Eastern Cape, South Africa The coordinate is the road-cutting's, published by Kitching and Raath in 1984 and reprinted by Norman and colleagues (2011), who also place the exposure on Farm Tulloch. Broom (1911) names the unit only as the Cave sandstone of the Stormberg Series.

References

  1. Broom, R. (1911). On the dinosaurs of the Stormberg, South Africa. Annals of the South African Museum 7(4): 291-308. broom1911a
  2. Sereno, P. C. (2012). Taxonomy, morphology, masticatory function and phylogeny of heterodontosaurid dinosaurs. ZooKeys 226: 1-225. Pensoft Publishers. doi:10.3897/zookeys.226.2840

    Assessed Geranosaurus among heterodontosaurids.

    sereno2012a
  3. Jones, B. (2026). The Princeton Encyclopedia of Dinosaurs: Ornithischians. Princeton University Press.

    Treats Geranosaurus as a dubious heterodontosaurid.

    jones2026a
  4. Norman, D. B.; Crompton, A. W.; Butler, R. J.; Porro, L. B.; Charig, A. J. (2011). The Lower Jurassic ornithischian dinosaur Heterodontosaurus tucki Crompton & Charig, 1962: cranial anatomy, functional morphology, taxonomy, and relationships. Zoological Journal of the Linnean Society 182-276. doi:10.1111/j.1096-3642.2011.00697.x

    Places the type locality on Farm Tulloch at Barkly Pass and reprints the coordinate Kitching and Raath published in 1984.

    norman2011a
  5. Bordy, E. M.; Abrahams, M.; Sharman, G. R.; Viglietti, P. A.; Benson, R. B. J.; McPhee, B. W.; Barrett, P. M.; Sciscio, L.; Condon, D.; Mundil, R.; Rademan, Z.; Jinnah, Z.; Clark, J. M.; Suarez, C. A.; Chapelle, K. E. J.; Choiniere, J. N. (2020). A chronostratigraphic framework for the upper Stormberg Group: implications for the Triassic-Jurassic boundary in southern Africa. Earth-Science Reviews 203: 103120. doi:10.1016/j.earscirev.2020.103120

    Dates the Clarens to a mainly Pliensbachian age on detrital zircons.

    bordy2020a