Open Paleo

Elemgasem

Baiano et al., 2022

Named after Elemgasem, a deity in Tehuelche mythology from the indigenous people of Patagonia; the name is taken directly from Tehuelche tradition

93.9–85.7 million years ago Turonian–Coniacian, Late Cretaceous
Late Cretaceous stages

Elemgasem is an extinct genus of brachyrostran abelisaurid from the Late Cretaceous Portezuelo Formation of Patagonia, Argentina. The genus contains a single species, Elemgasem nubilus. The cladistic position of Elemgasem within Brachyrostra is uncertain, given that phylogenetic analyses recover it as either a sister taxon to Furileusauria or in several positions within this clade.

Under dispute

Elemgasem is a brachyrostran whose exact position is uncertain; the describing analyses (Baiano and colleagues, 2022) recovered it either within Furileusauria or as its sister taxon, and it is an unstable taxon.

Diagnosis

  1. Marked rugosity formed by ridges and tubercles on the lateral surface of the proximal fibula (autapomorphy)
  2. Proximal high wall of the astragalus-calcaneum separating the tibia from the fibula when viewed laterally (autapomorphy)
  3. Dorsoventrally deep lateral surface of the calcaneum (autapomorphy)
  4. Posterior caudal vertebrae with oval articular surfaces of the centra, being transversely wider than dorsoventrally high
  5. Posterior caudal centra with an anteroposterior groove on the ventral surface

Species

Elemgasem nubilus Baiano et al., 2022

Type species

From Latin 'nubilus' meaning 'foggy' or 'foggy day', referring to the unusual foggy weather during the expedition that discovered the holotype.

Holotype
MCF-PVPH 380 , Museo ‘Carmen Funes’, Plaza Huincul
Material
Partial cervical epipophysis, middle and posterior caudal vertebrae (some fused/pathological), distal right femur, cnemial crest fragment, proximal fibulae, left astragalus-calcaneum, metatarsals II-IV fragments, pedal phalanges III-2, IV-2, IV-3, and pedal unguals II and III
Horizon
Portezuelo Formation, Turonian–Coniacian, Late Cretaceous , 93.9–85.7 million years ago
Locality
Sierra del Portezuelo, Neuquén, Argentina

References

  1. Baiano, M. A.; Pol, D.; Bellardini, F.; Windholz, G. J.; Cerda, I. A.; Garrido, A. C.; Coria, R. A. (2022). Elemgasem nubilus: a new brachyrostran abelisaurid (Theropoda, Ceratosauria) from the Portezuelo Formation (Upper Cretaceous) of Patagonia, Argentina. Papers in Palaeontology 8(5). Wiley. doi:10.1002/spp2.1462 baiano2022a
  2. Jones, B. (2026). The Princeton Encyclopedia of Dinosaurs: Theropods. Princeton University Press.

    Source of the mass and hip height estimates.

    jones2026c