Argulidae

The family Argulidae, whose members are commonly known as carp lice or fish lice, (not to be confused with Caligidae, also commonly referred to as sea lice) are parasitic crustaceans in the class Ichthyostraca. It is the only family in the monotypic subclass Branchiura and the order Arguloida, although a second family, Dipteropeltidae, has been proposed.