Pearlfish is the name of about 25 species of small, elongated fish found in tropical and warm waters. Most pearlfish are about 6 inches (15 centimeters) long, with a long dorsal fin and a long anal fin that meet at the tip of the pointed tail.
Pearlfish live as parasites (organisms that live in or on other organisms) or as part parasites in the body cavities of clams, sea cucumbers, sea urchins, starfish, and tunicates. Some species of pearlfish feed on the internal organs of the creatures they live inside. Pearlfish may get their name from one species that lives inside a pearl oyster’s shell. Alternatively, the name may come from pearlfishes’ silvery-white translucent coloring.
After hatching from the egg, a pearlfish passes through two distinct larval stages. The first larva is pelagic (swims in the surface water), the second larva is benthic (lives in or on the seabed).
