Remora

The remoras ( /ˈrɛmərəs/, scientific name Echeneidae), sometimes called suckerfishes, are a family of ray-finned fishes in the order Perciformes. They grow to 30–90 cm long (1–3 ft), and their distinctive first dorsal fins take the form of a modified oval sucker-like organ with slat-like structures that open and close to create suction and take a firm hold against the skin of larger marine animals. By sliding backward, the remora can increase the suction, or it can release itself by swimming forward. Remoras sometimes attach to small boats. They swim well on their own, with a sinuous, or curved, motion.