Genus · Troodontidae · Cretaceous

Troodon

Named by Leidy 1856

Troodon lived 83.6–66 million years ago, during the Campanian to Maastrichtian stages of the Late Cretaceous. The Paleobiology Database lists 103 fossil records for it from 4 countries (Canada, United States and Russia and others) — the 6th most of the 99 genera on this site.

Where it sits in time

Key facts from the records

Its records are spread over at least 10 formations; the largest share, 22%, is from the Dinosaur Park Formation.
It is one of the more widespread genera here: records from 4 countries, 11th of 99.
Saurornitholestes appears in 49% of the collections that hold Troodon; Dromaeosaurus in 24%.
Its stage range spans about 17.6 million years (15th longest of 99); it is the 3rd best-recorded of the 32 theropods here.

1 accepted species

Troodon has a single accepted species in PBDB.

Species	Named by	Records
Troodon formosus	Leidy 1856	55

Where it was found

103 records with coordinates.

Found alongside

Rock formations

States & provinces

Region	Records	Share
Alberta	55	53%
Montana	25	24%
Wyoming	8	8%
Alaska	5	5%
South Dakota	3	3%
North Dakota	2	2%
Amur	2	2%
Saskatchewan	1	1%

Country	Records	Share
Canada	56	54%
United States	43	42%
Russia	3	3%
China	1	1%

Records by stage

Well-dated records, by the stage of their mid-point age.

Campanian65
Maastrichtian32

Depositional settings

Crevasse splay16
Channel lag13
Channel10
Floodplain4
Wet floodplain3
Coarse channel fill3

Other theropods of its time

Same group, overlapping stage range, not found in the same collections.

Genus	Age	Country	Records
Tarbosaurus	72.1–66 Ma	Mongolia, China	56
Ornithomimus	83.6–66 Ma	United States, Canada	35
Albertosaurus	83.6–66 Ma	Canada, United States	32
Gallimimus	72.1–66 Ma	Mongolia, Uzbekistan	30
Masiakasaurus	72.1–66 Ma	Madagascar	29
Chirostenotes	83.6–66 Ma	United States, Canada	28
Majungasaurus	72.1–66 Ma	Madagascar	25
Daspletosaurus	83.6–72.1 Ma	United States, Canada	21

Also from these formations