Trierarchuncus fossil map
Where fossils of Trierarchuncus have been found, shown on the Earth as it looked about 66 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 66 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 | Theropods |
|---|---|
| Lived | 72.2–66 million years ago (Maastrichtian) |
| Periods | Cretaceous |
| Family | Alvarezsauridae |
| Named by | Fowler et al. 2020 |
| Fossil records | 6 occurrences at 5 locations (PBDB) |
| Found in | United States |
| Rock formations | Hell Creek |
About Trierarchuncus
Trierarchuncus (meaning "captain hook," after its single-clawed hands) is a monotypic genus of alvarezsaurid theropod which includes a single species, Trierarchuncus prairiensis, mainly known from fossils found in deposits of the Hell Creek Formation in Montana. It is the youngest known alvarezsaurid and one of the last non-avian dinosaurs, going extinct during the Cretaceous–Paleogene extinction event, which occurred approximately 66 million years ago.
Text in “About” is quoted from the Wikipedia article Trierarchuncus (revision 1341688358), 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: Q97120065.
