Perucetus fossil map
Where fossils of Perucetus have been found, shown on the Earth as it looked about 45 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 45 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 | 41.03–37.71 million years ago (Bartonian) |
| Periods | Paleogene |
| Family | Basilosauridae |
| Named by | Bianucci et al. 2023 |
| Fossil records | 2 occurrences at 1 locations (PBDB) |
| Found in | Peru |
| Rock formations | Paracas |
About Perucetus
Perucetus is an extinct genus of an early whale from Peru that lived during the Bartonian age of the middle Eocene. Perucetus is the largest Eocene whale, with length estimates varying from 15–16 meters (49–52 ft) to 17–20 meters (56–66 ft). It was initially claimed to have rivaled or exceeded the modern blue whale in weight, partly due to the incredibly thick and dense bones this animal possessed, coupled with its already great size, but subsequent studies argued that it was significantly lighter. The ecology of Perucetus also remains largely mysterious. Based on the fossils, it was likely a slow-moving inhabitant of shallow waters. Its diet can only be speculated, but one suggestion proposes that it may have fed on benthic animals like crustaceans and molluscs living on the ocean floor. Only a single species is currently known, P. colossus.
Text in “About” is quoted from the Wikipedia article Perucetus (revision 1372832562), 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: Q121095909.