Brontotholus fossil map
Where fossils of Brontotholus have been found, shown on the Earth as it looked about 75 million years ago and on today’s map.
Dots are fossil collections recorded in the Paleobiology Database. The “then” view moves today’s fossil sites back to their positions 75 million years ago (the time slice nearest the median age of the fossils) using the Merdith et al. (2021) plate model; positions are approximate. Open on the timeline map →
| Group | Horned & dome-headed dinosaurs |
|---|---|
| Lived | 83.6–72.2 million years ago (Campanian) |
| Periods | Cretaceous |
| Family | Pachycephalosauridae |
| Named by | Woodruff et al. 2025 |
| Fossil records | 4 occurrences at 4 locations (PBDB) |
| Found in | United States, Canada |
| Rock formations | Two Medicine, Oldman |
About Brontotholus
Brontotholus (lit. 'thunder dome') is an extinct genus of pachycephalosaurid dinosaur known from the Late Cretaceous (Campanian stage) Two Medicine and Oldman formations of Montana, United States, and Alberta, Canada, respectively. The genus contains a single species, Brontotholus harmoni, known from multiple partial domes.
Text in “About” is quoted from the Wikipedia article Brontotholus (revision 1367437603), licensed under CC BY-SA 4.0; introduction excerpted verbatim, formatting removed. Ages, family, authority and fossil records: Paleobiology Database, accessed 23 October 2026. Ages are those of the rock layers the fossils were found in. Wikidata: Q136465240.
