SEA HORSE

Sea horse (Hippocampus erectus). any of a number of species of small marine fishes of the family Syngnathidae (order Gasterosteiformes), found in warm seas. Sea horses are familiar animals, with their consecutive rings of body armour, their forward-curled, prehensile tails, and their horsey heads set at an angle to their bodies. They also have long, tubular snouts, small mouths, a single, soft-rayed dorsal fin, and eyes that can move independently of one another. Sea horses vary in size, ranging in length from about 4 to 30 cm (1 1/2 to 12 inches). Weak swimmers, sea horses usually live along the shore, among seaweed and other plants to which they cling by their tails. When swimming, they maintain an upright position, propelling themselves with their fins and rising or sinking by altering the volume of gas within their swim bladders. They catch and eat small organisms by sucking them quickly into their mouths. The reproductive behaviour of sea horses is notable in that the male, not the female, carries the fertilized eggs. The eggs, deposited in a brood pouch beneath the male's tail by the female, remain there until they hatch. At that time, the male contorts his body and expels the young through the single opening in the pouch. Sea horses are of interest as aquarium animals and as curios. They have also been used as heraldic emblems and to treat various ailments. Among the various species are: the dwarf sea horse (Hippocampus zosterae), an Atlantic form smaller than any other sea horse; H. ramulosus (or H. guttulatus), a brown sea horse of Europe; H. kuda, a large, brown or blackish Pacific sea horse; and H. whitei, a moderate-sized sea horse of Australia.