Genus
Valid Extinct

Duonychus

Kobayashi et al. 2025

Duonychus is an extinct genus of therizinosaurid theropod dinosaurs that lived during the Late Cretaceous of what is now Mongolia. It is known from a partial skeleton, including several vertebrae, most of the forelimbs, and part of the pelvic girdle, found in outcrops of the Bayanshiree Formation. The remains were discovered in 2012 by the Mongolian Academy of Sciences and briefly mentioned in later conference abstracts. The genus contains a single species, Duonychus tsogtbaatari, which was formally described in 2025.

Temporal range
Triassic
Jurassic
Cretaceous
Paleogene
Neogene
252 201 145 66 0 Ma
PBDB occurrences
1
Group
Dinosaures
Herbivore Ground dwelling Terrestrial
Duonychus
click to enlarge
Duonychus tsogtbaatari in Dinosaur Expo 2019 at Nationail Science Museum in Tokyo © ノボホショコロトソ · CC BY 4.0 · Wikimedia
Duonychus
Duonychus
PBDB Wikipedia
Classification
Dinosauria Unranked clade
Theropoda Unranked clade
Neotheropoda Unranked clade
Averostra Unranked clade
Tetanurae Unranked clade
Coelurosauria Unranked clade
Maniraptoriformes Unranked clade
Therizinosauria Unranked clade
Therizinosauroidea Superfamily
Therizinosauridae Family
Duonychus Genus
Fossil sites 1 geolocated sites
Distribution
Top countries
🇲🇳 Mongolia
1
Geological formations
Temporal distribution
Turonian (93.9–89.8 Ma)
1
Species (1)
Duonychus tsogtbaatari 101 Ma
Images 2
Bibliography
Original description
Y. Kobayashi, D. K. Zelenitsky, and A. R. Fiorillo, T. Chinzorig. 2025. Didactyl therizinosaur with a preserved keratinous claw from the Late Cretaceous of Mongolia. iScience DOI ↗
Bibliography (1)
Y. Kobayashi, D. K. Zelenitsky, and A. R. Fiorillo, T. Chinzorig. 2025. Didactyl therizinosaur with a preserved keratinous claw from the Late Cretaceous of Mongolia. iScience DOI ↗