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Gideonmantellia

Ruiz-Omeñaca et al., 2012 gih-dee-on-man-tell-ee-uh

Named after Gideon Mantell, the 19th-century English geologist and paleontologist who first described Iguanodon; the -ia suffix is a Latinized honorific form

125.8–121.4 million years ago Barremian, Early Cretaceous
Early Cretaceous stages

Gideonmantellia is an extinct genus of basal ornithopod dinosaur known from the Early Cretaceous (Barremian stage) Camarillas Formation of Galve, Province of Teruel, Spain. It contains a single species, Gideonmantellia amosanjuanae.

Under dispute

Its describers placed Gideonmantellia as a basal ornithopod more derived than Hypsilophodon (Ruiz-Omeñaca and colleagues, 2012), and Madzia and colleagues (2017) recover it as the basalmost branch within Ornithopoda, outside Iguanodontia. Fonseca and colleagues (2024) instead recover it within a restricted Hypsilophodontidae as the sister taxon of Hypsilophodon.

Diagnosis

  1. Postacetabular process of the ilium with a brevis shelf that is noticeably medially expanded in its cranial part but narrow and horizontal in its caudal part.
  2. Rod-like prepubic process with its anterior end twisted and expanded (lateral surface turns into dorsal surface distally).
  3. L-shaped (right-angle-bent) first chevron, unlike the straight or posteriorly curved first chevrons of other basal ornithischians.

Species

Gideonmantellia amosanjuanae Ruiz-Omeñaca et al., 2012

Type species

Named for the late paleontologist Olga María Amo Sanjuán, who studied the Cretaceous fauna of Galve, Spain.

Holotype
MPG-PBCH , Museo Paleontológico de Galve
Material
Partially articulated skeleton: nine dorsal, three sacral and twenty-one caudal vertebrae, dorsal rib fragments, six chevrons, ossified tendon fragments, left ilium, left prepubic process, left ischium and postpubis fragments, both femora, tibiae and fibulae, right astragalus, both calcanei, five metatarsals and nineteen pes phalanges.
Horizon
upper Camarillas Formation, Barremian, Early Cretaceous , 125.8–121.4 million years ago
Locality
Poyales, Teruel, Spain

References

  1. Ruiz-Omeñaca, J. I.; Canudo, J. I.; Cuenca-Bescós, G.; Cruzado-Caballero, P.; Gasca, J. M.; Moreno-Azanza, M. (2012). A new basal ornithopod dinosaur from the Barremian of Galve, Spain. Comptes Rendus Palevol 11(6): 435-444. Museum National D'Histoire Naturelle. doi:10.1016/j.crpv.2012.06.001 ruiz-omeñaca2012a
  2. Madzia, D.; Boyd, C. A.; Mazuch, M. (2017). A basal ornithopod dinosaur from the Cenomanian of the Czech Republic. Journal of Systematic Palaeontology 16(11): 967-979. Informa UK Limited. doi:10.1080/14772019.2017.1371258

    Recovered Gideonmantellia as a basal ornithopod outside Iguanodontia.

    madzia2017a
  3. Fonseca, A. O.; Reid, I. J.; Venner, A.; Duncan, R. J.; Garcia, M. S.; Müller, R. T. (2024). A comprehensive phylogenetic analysis on early ornithischian evolution. Journal of Systematic Palaeontology 22: 2346577. doi:10.1080/14772019.2024.2346577

    Recovered Gideonmantellia within a restricted Hypsilophodontidae, sister to Hypsilophodon.

    fonseca2024a
  4. Jones, B. (2026). The Princeton Encyclopedia of Dinosaurs: Ornithischians. Princeton University Press.

    Treats Gideonmantellia as a basal ornithopod outside Iguanodontia.

    jones2026a