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Basilosaurus fossil map

Where fossils of Basilosaurus have been found, shown on the Earth as it looked about 30 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 30 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 →

Basilosaurus
Image: Tim from Washington, D.C., United States of America, CC BY-SA 2.0, via Wikimedia Commons
GroupEarly mammals
Lived56–33.9 million years ago (Ypresian to Priabonian)
PeriodsPaleogene
FamilyBasilosauridae
Named byHarlan 1834
Fossil records89 occurrences at 79 locations (PBDB)
Found inUnited States, Egypt, Western Sahara, Ukraine, Jordan, Poland
Rock formationsYazoo, txn:42936, Birket Qarun, Ocala, Samlat, Gehannam

About Basilosaurus

Basilosaurus (meaning "king lizard") is a genus of large, predatory, prehistoric archaeocete whale from the late Eocene, approximately 41.3 to 33.9 million years ago (mya). First described in 1834, it was the first archaeocete and prehistoric whale known to science. Fossils attributed to the type species B. cetoides were discovered in the southeastern United States. The generic name, meaning "king lizard", was given due to the initial misconception about the fossil material as that of a giant reptile. The animal was later found to be an early marine mammal, prompting attempts at renaming the creature, which failed as the rules of zoological nomenclature dictate using the original name given. The second species named in 1904, B. isis, lived in the region currently known as the Mediterranean Sea, with fossils found in North Africa and Jordan.

Text in “About” is quoted from the Wikipedia article Basilosaurus (revision 1381174565), licensed under CC BY-SA 4.0; introduction excerpted verbatim, formatting removed. Ages, family, authority and fossil records: Paleobiology Database, accessed 22 October 2026. Ages are those of the rock layers the fossils were found in. Wikidata: Q134884.

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