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Troodon formosus Leidy 1856 (coelurosaur)

Reptilia - Avetheropoda - Troodontidae

PaleoDB taxon number: 54818

Synonyms: Polyodontosaurus grandis Gilmore 1932 (no. 54471), Saurornithoides inequalis Sternberg 1932 (no. 63716), Stenonychosaurus inequalis Sternberg 1932 (no. 54467), Troodon inequalis Sternberg 1932 (no. 96129)

Full reference: J. Leidy. 1856. Notices of remains of extinct reptiles and fishes, discovered by Dr. F. V. Hayden in the bad lands of the Judith River, Nebraska Territory. Proceedings of the Academy of Natural Sciences of Philadelphia 8:72-73

Belongs to Troodon according to B. R. Peecook and C. A. Sidor 2015

Sister taxa: none

Type specimens:

  • Troodon formosus: ANSP 9259, a tooth. Its type locality is Judith River badlands (USGS), which is in a Campanian/Campanian terrestrial horizon in the Judith River Formation of Montana.
  • Polyodontosaurus grandis: NMC 8540, a mandible. Its type locality is Polyodontosaurus type, RTMP (NMC), which is in a Campanian terrestrial horizon in the Dinosaur Park Formation of Canada.
  • Stenonychosaurus inequalis: NMC 8539. Its type locality is 1.5 miles southwest of mouth, Berry Creek, which is in a Campanian terrestrial horizon in Canada.

Ecology: ground dwelling carnivore-omnivore

Average measurements (in mm): femur length 126.0, tibia 315.0 x 58.6, ulna length 134.5

Estimated body mass: 5.90 kg based on femur length