Brittle starOphiuroidea

Brittle stars (Ophiuroidea) are echinoderms with a distinct, often flattened central disk from which five long, slender, flexible arms radiate. These arms are clearly demarcated from the disk, which houses all internal organs, and can reach up to 60 cm (24 in) in length. Colouration is typically cryptic, ranging from plain browns and greens to mottled patterns. Ophiuroidea derives from the Greek for 'snake-like', referring to their flexible arms, while the common name reflects their ability to readily shed arm segments as a defence.

They are common inhabitants of 🌊 Red Sea reef flats, slopes, and soft bottoms, found from shallow waters down to at least 300 m (1000 ft). Most species crawl across the seafloor, hiding under rocks, in crevices, or within sponges and corals during the day, emerging at night to feed. The mouth, located on the underside of the disk, is ringed with five toothed jaws, used for both ingesting food and expelling waste. Diets vary; many are scavengers or detritivores, moving organic particles with their tube feet, while others prey on small crustaceans or worms. Basket stars, a subgroup, are suspension feeders that extend mucus-coated arms to trap plankton. Though most lack eyes, they sense chemicals, touch, and light with nerve endings and tube feet, particularly at their arm tips.