Rock formation · Cretaceous · Canada, United States
St. Mary River Formation
The St. Mary River Formation holds 5 genera from this site (20th of 26 formations), in 9 fossil records. Its dinosaur-bearing records date to the Maastrichtian (72.1–66 Ma), with finds in Alberta and Montana.
Genera recorded here
Records in this formation, and the share of each genus's total records that come from it.
| Genus | Records here | Age | Group | Share of genus |
|---|---|---|---|---|
| Pachyrhinosaurus | 4 | 83.6–66 Ma | Horned dinosaurs | 25% |
| Edmontosaurus | 2 | 72.1–66 Ma | Ornithopods | 2% |
| Edmontonia | 1 | 83.6–66 Ma | Armoured & plated dinosaurs | 6% |
| Euoplocephalus | 1 | 83.6–72.1 Ma | Armoured & plated dinosaurs | 6% |
| Troodon | 1 | 83.6–66 Ma | Theropods | 1% |
Age ranges of its genera
Overall stage range of each genus (all formations).
Where it crops out
Fossil records with coordinates.
Groups present
Armoured & plated dinosaurs (2), ornithopods (1), horned dinosaurs (1), theropods (1).