Cimexomys fossil map
Where fossils of Cimexomys 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 | Early mammals |
|---|---|
| Lived | 85.7–63.4 million years ago (Santonian to Danian) |
| Periods | Cretaceous, Paleogene |
| Named by | Sloan and Van Valen 1965 |
| Fossil records | 112 occurrences at 31 locations (PBDB) |
| Found in | United States, Canada |
| Rock formations | Hell Creek, Lance, Fort Union, Oldman, Judith River, Wahweap |
About Cimexomys
Cimexomys is an extinct North American mammal that lived from the Upper Cretaceous to the Paleocene. For a while, it shared the world with dinosaurs, but outlived them. It was a member of the extinct order Multituberculata and lies within the suborder Cimolodonta. It is perhaps a member of the Paracimexomys group, though it is not certain.
The genus Cimexomys ("bug mouse") was named by Sloan and Van Valen in 1965. Most remains are restricted to teeth. "Cimex" means "bug", with reference to the type locality of Cimexomys minor in the Bug Creek Anthills in Montana, United States.
The inclusion of Cimexomys in the Paracimexomys group is tentative, (Kielan-Jaworowska & Hurum, 2001, p. 403). Some species are termed here as "Cimexomys", and they're listed towards the end. New species have previously been christened with great enthusiasm, and much reidentification has also occurred.
Text in “About” is quoted from the Wikipedia article Cimexomys (revision 1283167989), 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: Q5120126.
