Nothronychus

Nothronychus
Temporal range: Late Cretaceous (Turonian) 93.9–89.8 Ma
[1]
Reconstructed skeleton of N. mckinleyi
Scientific classification Edit this classification
Domain: Eukaryota
Kingdom: Animalia
Phylum: Chordata
Clade: Dinosauria
Clade: Saurischia
Clade: Theropoda
Superfamily: Therizinosauroidea
Family: Therizinosauridae
Genus: Nothronychus
Kirkland & Wolfe, 2001
Type species
Nothronychus mckinleyi
Kirkland & Wolfe, 2001
Other species
  • N. graffami
    Zanno et al., 2009

Nothronychus (meaning "slothful claw") is a genus of therizinosaurid theropod dinosaurs that lived in North America during the Late Cretaceous period. The type species, Nothronychus mckinleyi, was described by James Kirkland and Douglas G. Wolfe in 2001. It was recovered near New Mexico's border with Arizona, in an area known as the Zuni Basin, from rocks assigned to the Moreno Hill Formation, dating to the Turonian stage of the Late Cretaceous. A second specimen, described in 2009 as a second species, Nothronychus graffami, was found in the Tropic Shale of Utah, dating between one million and a half million years older than N. mckinleyi.

Nothronychus were bulky herbivorous theropods with wide, sloth-like hip (resembling that of the non-related ornithischians), four-toed feet with all four toes facing forward, elongated necks and prominent arms with sharp claws. Both species were similar in dimensions, but N. graffami was slightly more robust than N. mckinleyi.

  1. ^ Cilliers, Charl D.; Tucker, Ryan T.; Crowley, James L.; Zanno, Lindsay E. (2021). "Age constraint for the Moreno Hill Formation (Zuni Basin) by CA-TIMS and LA-ICP-MS detrital zircon geochronology". PeerJ. 9. e10948. doi:10.7717/peerj.10948. PMC 7953880. PMID 33854833.