Leptocyon fossil map
Where fossils of Leptocyon have been found, shown on the Earth as it looked about 15 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 15 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 | 29.5–4.7 million years ago (Rupelian to Zanclean) |
| Periods | Paleogene, Neogene |
| Family | Canidae |
| Named by | Matthew 1918 |
| Fossil records | 266 occurrences at 60 locations (PBDB) |
| Found in | United States, Canada |
| Rock formations | Valentine, txn:41189, Ash Hollow, Barstow, Harrison, Runningwater |
About Leptocyon
The genus Leptocyon (Greek: leptos slender + cyon dog) includes 11 species and is the oldest known canine. They were small and weighed around 2 kilograms (4.4 lb). They first appeared in North America around 34 million years ago in the Oligocene, at the same time as the Borophaginae, with whom they share features, indicating that these were two sister groups. Borophaginae skull and dentition were designed for a powerful killing bite compared with the Leptocyon which were designed for snatching small, fast-moving prey. The species L. delicatus is the smallest canid to have existed. At the close of their genus 9 million years ago one Leptocyon lineage resembled the modern fox.
Leptocyon were small-bodied, fox-like animals with a long, narrow jaw and delicate teeth. They were probably omnivorous, feeding on small animals and fruit in a diet that remained relatively unchanged during the Miocene.
Text in “About” is quoted from the Wikipedia article Leptocyon (revision 1313221517), 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: Q138900.
