Open Paleo

Quilmesaurus

Coria, 2001 keel-may-SAWR-us Disputed

Named for the Quilmes, an indigenous people of northwestern Argentina, combined with Greek 'sauros' meaning 'lizard'.

83.6–66.0 million years ago Campanian–Maastrichtian, Late Cretaceous
Late Cretaceous stages

Quilmesaurus is a genus of carnivorous theropod dinosaur from the Upper Cretaceous (Campanian to Maastrichtian stages) Allen Formation of Argentina. It was a member of Abelisauridae, closely related to genera such as Carnotaurus. The only known remains of this genus are leg bones which share certain similarities to a variety of abelisaurids. However, these bones lack unique features, which may render Quilmesaurus a nomen vanum (more commonly known as a nomen dubium, or "dubious name").

Under dispute

Juárez Valieri and colleagues (2007) referred Quilmesaurus to Abelisauridae (tentatively Carnotaurinae) but regarded it as a nomen vanum — an invalid name lacking unambiguous autapomorphies — though numerous subsequent studies continue to treat it as a valid furileusaurian abelisaurid.

Diagnosis

  1. Femur with strong, well-developed mediodistal crest extending as broad anteromedially projecting lamina
  2. Tibia with hook-shaped cnemial crest, distal end of cnemial crest noticeably expanded with distinctive hook-like shape in medial view
  3. Lateral malleolus twice the size of medial malleolus, resulting in asymmetrical distal tibial profile
  4. Low facet for the ascending process of the astragalus (16% of tibia length)
  5. Fossa on the distal articular surface of the tibia

Species

Quilmesaurus curriei Coria, 2001 Disputed

Type species

Named for Dr. Philip John Currie, a Canadian theropod specialist.

Holotype
MPCA-PV 100 , Museo provincial de Cipolletti "Carlos Ameghino"
Material
Distal right femur and complete right tibia
Horizon
lower Allen Formation, Campanian–Maastrichtian, Late Cretaceous , 83.6–66.0 million years ago
Locality
Salitral Ojo de Agua, Río Negro, Argentina

References

  1. Coria, R. A. (2001). New theropod from the Late Cretaceous of Patagonia. Mesozoic Vertebrate Life: New Research Inspired by the Paleontology of Philip J. Currie (Tanke, D. H.; Carpenter, K., eds.) 3-9. Indiana University Press, Bloomington. coria2001a
  2. Juárez Valieri, R. D.; Fiorelli, L. E.; Cruz, L. E. (2007). Quilmesaurus curriei Coria, 2001 (Dinosauria, Theropoda). Su validez taxonómica y relaciones filogenéticas [Its taxonomic validity and phylogenetic relationships]. Revista del Museo Argentino de Ciencias Naturales 9(1): 59-66. doi:10.22179/revmacn.9.367

    Referred Quilmesaurus to Abelisauridae (tentatively Carnotaurinae) and regarded it as a nomen vanum for lacking autapomorphies.

    juárezvalieri2007a
  3. Jones, B. (2026). The Princeton Encyclopedia of Dinosaurs: Theropods. Princeton University Press.

    Source of the mass and hip height estimates.

    jones2026c