What is "brittle star"

Brittle star \Brit"tle star`\ (br[i^]t"t'l st[aum]r`), (Zo["o]l.) Any species of ophiuran starfishes. See Ophiuroidea.

n. any of various echinoderms, of the class Ophiuroidea, that resemble starfish and have long, slender arms that regenerate when snapped off

n. an animal resembling a starfish with fragile whiplike arms radiating from a small central disc [syn: brittle-star, serpent star]

Brittle stars or ophiuroids are echinoderms in the class Ophiuroidea closely related to starfish. They crawl across the sea floor using their flexible arms for locomotion. The ophiuroids generally have five long, slender, whip-like arms which may reach up to in length on the largest specimens. They are also known as serpent stars; the New Latin class name Ophiuroidea is derived from the Ancient Greek ὄφις, meaning "serpent".

The Ophiuroidea contain two large clades, Ophiurida (brittle stars) and Euryalida (basket stars). Many of the ophiuroids are rarely encountered in the relatively shallow depths normally visited by humans, but they are a diverse group. Over 2,000 species of brittle stars live today. More than 1200 of these species are found in deep waters, greater than 200 m deep.