Timingila Fish
Region of origin: India
Literally “to swallow a whale,” the timingila was known as an aquatic creature supposedly large enough to do just that in a single gulp. It was never specifically decsibed but was mentioned in the Mahabharata and several other Sanskrit texts, and has since been compared to a shark- or whale-like creature which dwarfed any known species, similar to stories of the leviathan.
The Compendium of Arcane Beasts and Critters 