| Named By: | Lambert et al. in 2010. Homonym: Leviathan melvillei |
| Time Period: | Tortonian (Chasicoan)~9.9-8.9 Ma (possible Zanclean occurrence) |
| Location: | Peru - Pisco Formation |
| Size: | Skull is 3 meters long. Total size estimates vary between 13.5 and 17.5 meters long |
| Diet: | Carnivore |
| Fossil(s): | Partial preserved skull, mandible (lower jaw) and teeth |
| Classification: | | Chordata | Mammalia | Cetacea | Physeteroidea | |
Livyatan is an extinct genus of physeteroid whale, similar in size to the modern sperm whale. It contains the single species L. melvillei. It lived during the Tortonian stage of the Miocene epoch, about 9.9-8.9 million years ago (Mya), though evidence from Australia implies that either it or a close relative survived into the Zanclean stage of the Pliocene, around 5 Mya.