Geranosaurus

Extinct genus of dinosaurs

Geranosaurus Temporal range: Early Jurassic, ~190–182 Ma PreꞒ Ꞓ O S D C P T J K Pg N

Holotype jaw
Scientific classification
Domain:	Eukaryota
Kingdom:	Animalia
Phylum:	Chordata
Clade:	Dinosauria
Clade:	†Ornithischia
Family:	†Heterodontosauridae
Genus:	†Geranosaurus Broom, 1911
Type species
†Geranosaurus atavus Broom, 1911

Geranosaurus (meaning "crane reptile") is a genus of heterodontosaurid ornithischian dinosaur from the Early Jurassic. The type and only species is G. atavus.

Description

Geranosaurus is known only from crushed fragments of the skull, a single jaw bone with nine tooth stubs and limb elements discovered in the Clarens Formation, South Africa in 1871. It was around 0.6 metres (2.0 ft) tall and around 1.2 metres (3.9 ft) long when fully grown.^[1]^[2]

The type species, G. atavus, was described by Robert Broom in 1911.^[2] The genus name is derived from Greek geranos, "crane", a reference to the crane-like hind-limb. The specific name means "ancestor" in Latin. The limb elements have inventory number SAM 1871.^[2]

Classification

Geranosaurus is classified as an ornithischian based on the jaw, probably a heterodontosaurid distinct from Heterodontosaurus^[1] but not a heterodontosaurine.^[3] Because of its limited remains, Geranosaurus is generally considered a nomen dubium,^[1] but it may be distinct because it has the unique combination of an enlarged dentary caniniform, which is a synapomorphy of Heterodontosauridae, and no post-caniniform diastema, which excludes it from Heterodontosaurinae.^[3]

References

^ ^a ^b ^c Sereno, Paul C. (2012-10-03). "Taxonomy, morphology, masticatory function and phylogeny of heterodontosaurid dinosaurs". ZooKeys (223): 1–225. Bibcode:2012ZooK..226....1S. doi:10.3897/zookeys.223.2840. ISSN 1313-2989. PMC 3491919. PMID 23166462.
^ ^a ^b ^c R. Broom, 1911, "On the dinosaurs of the Stormberg, South Africa", Annals of the South African Museum 7(4): 291-308
^ ^a ^b Fonseca, André O.; Reid, Iain J.; Venner, Alexander; Duncan, Ruairidh J.; Garcia, Mauricio S.; Müller, Rodrigo T. (2024-12-31). "A comprehensive phylogenetic analysis on early ornithischian evolution". Journal of Systematic Palaeontology. 22 (1). doi:10.1080/14772019.2024.2346577. ISSN 1477-2019.