Open Paleo

Deinocheirus

Kielan-Jaworowska, 1969 DY-no-KY-ruhs /ˌdaɪnoʊˈkaɪrəs/

From Greek deinos, 'terrible/horrible', + Greek cheir, 'hand'; means 'horrible hand', named for the enormous arms and hands first discovered

72.2–66.0 million years ago Maastrichtian, Late Cretaceous
Late Cretaceous stages

Deinocheirus is a genus of large ornithomimosaur that lived during the Late Cretaceous around 70 million years ago. In 1965, a pair of large arms, shoulder girdles, and a few other bones of a new dinosaur were first discovered in the Nemegt Formation of Mongolia. In 1970, this specimen became the holotype of the only species within the genus, Deinocheirus mirificus; the genus name is Greek for "horrible hand". No further remains were discovered for almost fifty years, and its nature remained a mystery. Two more complete specimens were described in 2014, which shed light on many aspects of the animal. Parts of these new specimens had been looted from Mongolia some years before, but were repatriated in 2014.

Species

Deinocheirus mirificus Kielan-Jaworowska, 1969

Type species

From Latin 'mirificus' meaning 'unusual' or 'peculiar', chosen for the highly unusual structure of the animal's enormous forelimbs.

Holotype
MPC-D 100/18 , Paleontological Center, Mongolian Academy of Sciences
Horizon
Nemegt Formation, Maastrichtian, Late Cretaceous , 72.2–66.0 million years ago
Locality
Altan Uul III, Ömnögovi, Mongolia

Notable specimens

  • MPC-D 100/127

    Paleontological Center, Mongolian Academy of Sciences Found 2009 gut contents

    Found at Bügiin Tsav, this near-complete specimen preserved more than 1,400 gastroliths among its ribs and gastralia, including fish vertebrae and scales that indicate omnivory. Reunited with poached, repatriated skull, hand, and feet, it yielded the first known Deinocheirus skull.

    Lee et al. (2014)

  • MPC-D 100/128

    Paleontological Center, Mongolian Academy of Sciences Found 2006 complementary

    A subadult, only 74 percent the size of the largest individual, collected at the Altan Uul IV locality. It fills most gaps left by specimen MPC-D 100/127, preserving nearly all dorsal and caudal vertebrae, the ilium, a partial ischium, and most of the left hindlimb.

    Lee et al. (2014)

References

  1. Kielan-Jaworowska, Z. (1969). Fossils from the Gobi desert. Science Journal 5(1): 32-38. kielan-jaworowska1969a
  2. Jones, B. (2026). The Princeton Encyclopedia of Dinosaurs: Theropods. Princeton University Press.

    Source of the appearance features.

    jones2026c
  3. Lee, Y. N.; Barsbold, R.; Currie, P. J.; Kobayashi, Y.; Lee, H. J.; Godefroit, P.; Escuillié, F. O.; Chinzorig, T. (2014). Resolving the long-standing enigmas of a giant ornithomimosaur Deinocheirus mirificus. Nature 515(7526): 257-260. doi:10.1038/nature13874 lee2014a