Echeneidae

(remoras), a family of fishes of the suborder Echeneiformes of the order Perciformes. The fishes are sometimes regarded as a separate order. The seven genera, embracing seven species, are widely distributed in the tropical and subtropical waters of the Pacific Ocean. The head bears an oval suctorial disk (a modified anterior dorsal fin), which is surrounded by an elastic muscular ridge. Remoras attach themselves by means of the sucker to other fishes (for example, sharks), turtles, cetaceans, and, sometimes, the bottom of ships. The degree of attachment to the host varies in different species. For example, the shark sucker (Echeneis naucrates), the largest species (over 90 cm long), is able to swim alone, whereas the remora (Remora remora) is perpetually attached to a large shark. Echeneidae feed on free-swimming planktonic organisms and, to a lesser degree, on ectoparasites of their hosts. The young do not require a host.