Gorgonocephalidae Family of Basket Stars

Two Basket Stars of the Gorgonocephalidae Family can be found in this website:

Phylogeny: Basket Stars of the Gorgonocephalidae Family are members of the Echinodermata phylum and the Asterozoa subphylum. This means that they are star-shaped animals with radial symmetry, a water vascular system, and spiny skin. They are in the Ophiuroidea class of brittle stars, the Myophiuroida subclass, the Metophiurida infraclass, and the Euryopiurida superorder. The Gorgonocephalidae Family is one of three families in the order Euryalida. The Gorgonocephalidae Family is fairly large and consists of four subfamilies, thirty-two genera, and around ninety-five species. Species in the Gorgonocephalidae Family are also commonly called Gorgonocephalids and Snake Stars.

Morphology: Gorgonocephalid Basket Stars have a central disk-like body encircled by five repeatedly branching arms. When contracted, the arms look like a mass of entangled snakes. When extended the animal resembles a woven basket. The dorsal surface of these arms are covered by a row of very small hooks that are used for trapping food. They are covered by a soft, rubbery, and tuberculate skin. For structural support, they have an internal skeleton made of calcified ossicles. As brittle stars, their tube feet lack suckers or ampullae. Gorgonocephalids vary greatly in size from arm lengths of around 2.5 cm (1 inch) to 70 cm (27.5 inches). The central disk of the largest specimens can reach 14 cm (5.5 inches) in diameter.

Habitat and Distribution: Basket Stars may be found on hard substrates or on other animals such as soft corals or sponges. They generally prefer areas with moderate to strong current. Basket Stars live at depths ranging from 5 m (16 feet) to 2,000 m (6,560 feet). Basket Stars are found worldwide in polar to tropical seas. Three species from the Gorgonocephalidae Family are found in Mexican waters.

Reproduction: Spiny Basket Stars are gonochoric (male or female for life). Reproduction is sexual, through broadcast spawning, with external fertilization. Some species brood their embryos.  The embryos develop in bursae, which act as brood chambers where the embryos develop into juveniles and later crawl out from the bursal slits. After their planktonic larval stage they metamorphose into basket stars and settle to the bottom. They can also reproduce asexually through regeneration of severed body parts or fissiparity (voluntary dividing of the central disk).

Ecosystem Interactions: Basket Stars feed by climbing high on to gorgonians or other perches and extending their many arms to form a net. This net captures small prey that is being swept by in the current. Once the prey is grasped by the barbs, it is encased in mucous and then passed to the mouth. Prey includes planktonic crustaceans, fish larvae, jellyfish and worms. They feed primarily at night. In turn, Basket Stars are preyed upon by crabs and fish. They have few predators due to their low nutritive value. To avoid predation they can crawl to cover, roll up their arms to make them harder to bite, or break off an arm to save the rest of the animal.