Open Paleo

Megaraptor

Novas, 1998 meg-a-RAP-tor

From Greek 'megas' (large) and Latin 'raptor' (one who seizes or thief); meaning 'large thief' or 'large raptor'

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

Megaraptor is a genus of large theropod dinosaur, the type genus and namesake of the clade Megaraptora and family Megaraptoridae. Its fossils have been discovered in the Patagonian Portezuelo Formation of Argentina, South America, dating to the Turonian and Coniacian ages of the Late Cretaceous, roughly 90-88 million years ago. One species of Megaraptor, M. namunhuaiquii, has thus been named, known from seven partial or fragmentary skeletons, with only two including skull elements.

Diagnosis

  1. Blade-like olecranon process on proximal ulna
  2. Distal end of ulna stout and triangular in distal aspect
  3. Manual phalanx 1.I subquadrangular in proximal view, with dorsal portion transversely wider than ventral
  4. Metatarsal III with deep and wide extensor ligament pit

Species

Megaraptor namunhuaiquii Novas, 1998

Type species

From the Mapuche 'namun' meaning 'foot' and 'huaiqui' meaning 'lance', referring to the large claw initially believed to come from the foot.

Holotype
MCF-PVPH 79 , Museo ‘Carmen Funes’, Plaza Huincul
Material
Right ulna, left manual phalanx 1.I, distal half of right metatarsal III, ungual phalanx of digit II of the right pes
Horizon
Portezuelo Formation, Turonian–Coniacian, Late Cretaceous , 93.9–85.7 million years ago
Locality
Sierra del Portezuelo, Neuquén, Argentina

Notable specimens

  • MUCPv 341

    Universidad Nacional del Comahue complementary

    Second known specimen: a right ulna, radius and complete manus found in association with a Futalognkosaurus femur. It demonstrated that the large ungual belonged to the first manual digit rather than the second pedal digit, overturning the holotype interpretation and revealing the hand anatomy.

    Calvo et al. (2004)

  • MUCPv 595

    Universidad Nacional del Comahue complementary

    A juvenile about 3 m long and around six years old by bone histology, with a partial skull, much of the neck and trunk, and both shoulder girdles and upper arms. It gave the first look at the skull of Megaraptor, and Paulina-Carabajal and Porfiri (2025) later CT-scanned its braincase.

    Porfiri et al. (2014)Paulina-Carabajal & Porfiri (2025)

References

  1. Novas, F. E. (1998). Megaraptor namunhuaiquii, gen. et sp. nov., a large-clawed, Late Cretaceous theropod from Patagonia. Journal of Vertebrate Paleontology 18(1): 4-9. Informa UK Limited. doi:10.1080/02724634.1998.10011030 novas1998a
  2. Jones, B. (2026). The Princeton Encyclopedia of Dinosaurs: Theropods. Princeton University Press.

    Source of the appearance features.

    jones2026c
  3. Calvo, J. O.; Porfiri, J. D.; Veralli, C.; Novas, F. E.; Poblete, F. (2004). Phylogenetic status of Megaraptor namunhuaiquii Novas based on a new specimen from Neuquén, Patagonia, Argentina. Ameghiniana 41: 565-575. calvo2004b
  4. Porfiri, J. D.; Novas, F. E.; Calvo, J. O.; Agnolín, F. L.; Ezcurra, M. D.; Cerda, I. A. (2014). Juvenile specimen of Megaraptor (Dinosauria, Theropoda) sheds light about tyrannosauroid radiation. Cretaceous Research 51: 35-55. doi:10.1016/j.cretres.2014.04.007

    Describes the juvenile MUCPv 595, the first specimen of Megaraptor with skull material, and dates it to about six years old from bone histology.

    porfiri2014a
  5. Paulina-Carabajal, A.; Porfiri, J. D. (2025). Novel information on the braincase of Megaraptor namunhuaiquii (Dinosauria: Theropoda) using X-ray tomography: pneumaticity, paleoneurology, and their paleobiological implications. Ameghiniana 63(1): 16-32. doi:10.5710/AMGH.18.10.2025.3657

    Redescribes the braincase of the juvenile MUCPv 595 from micro-CT data, with its endocast, inner ear and pneumatic recesses.

    paulina-carabajal2025a