Koparion

Chure, 1994 ko-PAYR-ee-on Nomen dubium

From Ancient Greek 'koparion' (small surgical knife), referring to the small, blade-like shape of the known tooth fossil

154.8–143.1 million years ago Kimmeridgian–Tithonian, Late Jurassic

Late Jurassic stages

Koparion is a genus of small coelurosaurian theropod dinosaur, from the late Jurassic Period (Kimmeridgian stage), of Utah. It contains the single named species Koparion douglassi which is known only from a single isolated tooth.

Under dispute

Koparion douglassi is based on a single maxillary tooth from the Morrison Formation and is a tooth-based taxon; its describer referred it to Troodontidae on dental characters (Chure, 1994), but it cannot be placed more precisely and is treated by some as of doubtful validity. It is placed at Troodontidae incertae sedis.

Species

Koparion douglassi Chure, 1994 Nomen dubium

Type species

Named for Earl Douglass, who in the early twentieth century excavated the Dinosaur National Monument quarry near where the holotype tooth was discovered.

Holotype: DINO 3353 , Dinosaur National Monument
Material: Single maxillary tooth crown (root missing)
Horizon: upper Brushy Basin Member, Morrison Formation, Kimmeridgian–Tithonian, Late Jurassic , 154.8–143.1 million years ago The age of the containing rock unit; no finer age has been published.
Locality: DNM 94, Utah, United States

References

Chure, D. J. (1994). Koparion douglassi, a new dinosaur from the Morrison Formation (Upper Jurassic) of Dinosaur National Monument; the oldest troodontid (Theropoda: Maniraptora). Brigham Young University Geology Studies 40: 11-15. chure1994a