With its overlapping, fan-shaped scales, broad, blunt snout, and torpedo-like body, the Australian lungfish looks like it swam right out of the Paleozoic era. And in a way, it did: Fossil records show its ancient ancestors appearing on the scene 380 million years ago, making Neoceratodus one of the oldest living genera of backboned animals on Earth—and the closest living relative to the first fish that crawled out of the sea.
The clue to N. forsteri’s other main claim to fame lies in its name: It has a lung! The vast majority of fish species don’t have lungs and breathe with their gills, but the Australian lungfish can supplement its oxygen intake by gulping air at the surface. This usually only occurs when water levels are low, water quality is poor, or during periods of unusual activity—like spawning season.