remora, any of the several species of warmwater fishes of the family Echeneidae, characterized by an oval sucking disk on the top of the head. With this apparatus (a modification of the dorsal fin) the remora, or suckerfish, attaches itself to sharks, swordfishes, drums, marlins, and sea turtles. In this way it travels without effort, feeding on scraps from the prey of these larger creatures and in some cases on their crustacean parasites. Remoras sometimes attach themselves to small boats, but they can also swim well on their own. The adhesive power of their sucking disks is so great that the natives of some tropical regions use remoras to catch sea turtles by attaching lines to their tails. Different species prefer different hosts. The whalesucker, Remilegia australis, is usually found attached to whales. The smallest remora, the 7 in. (18 cm) Remoropsis pallidus, prefers swordfishes and tuna. Largest and most common is the shark remora, or sharksucker, which reaches 3 ft (90 cm) in length and attaches itself to sharks; it is found along the Atlantic coast N of Long Island in the summer. Remoras are classified in the phylum Chordata, subphylum Vertebrata, class Osteichthyes, order Echeniformes, family Echeneidae.

or sharksucker or suckerfish

Any of 8–10 species of marine fishes (family Echeneidae) noted for attaching themselves to, and riding about on, sharks, other marine animals, and oceangoing ships. Remoras adhere by means of a flat, oval sucking disk on top of the head. They are thin and dark, 1–3 ft (30–90 cm) long. They live in warm waters worldwide, feeding on the leavings or the external parasites of their hosts.

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