Hexanchidae
Hexanchidae is a family of sharks commonly known as sixgill or sevengill sharks. These sharks are characterized by having six or seven gill slits on each side of their heads, a feature that distinguishes them from most other shark species which have five. They are ancient lineages, with fossil evidence dating back to the Jurassic period. Hexanchids are found in deep waters around the world, typically inhabiting continental slopes and seamounts.
There are currently three recognized genera within the Hexanchidae family: Hexanchus, Notorychus, and Heptranchias. The genus
Hexanchid sharks are slow-moving predators, feeding on a variety of prey including fish, crustaceans, cephalopods, and