Bocas Species Database

Habitat: All coral reef zones, seagrass and mangrove areas, and in fouling communities on marine structures and ships' bottoms.   Distribution: In warm waters throughout the Indo-Pacific, eastern Pacific, and on both sides of the Atlantic. Caribbean and Gulf of Mexico.   Natural History Notes: The distribution of O. savignyi is large and it has been described as "the most common brittle star in the world" (H. L. Clark 1933). Within sponges, it reaches extremely high densities of up to 3,000 individuals per liter and 855 individuals per sponge. It is capable of reproducing both asexually and sexually. Asexual reproduction occurs by fission. After the splitting event, two arms grown from the healed edge of the disk and a third arm bud arises in the space between them. Sexual reproduction occurs in larger individuals (over 4mm in disk diameter). Females produce up to 10,000 oocytes of 0.1 mm diameter. The ophiopluteus of the species has been described, but the larva has not been reared through metamorphosis. The species lives in algae, corals, sponges, and rubble.   Depth: Usually in shallow water, but reported to 518 m.   Characteristics: O. savignyi has six-arms. Its disk is typically 3.8 mm in diameter, and its arms are 16.3 mm long. On larger specimens, small rough-tipped spines can be seen scattered over the disk. The species has five to six arm spines. The vental spine is relatively small; the others are roughly the same size. Individuals are greenish, greenish brown, brown and cream.