Common Brittle Star

The common brittle star is extremely variable in colouration, ranging from violet, purple or red to yellowish or pale grey, often spotted with red. The arms are usually white or grey with pink bands. The central disc is about one centimetre in diameter with the five arms being about five times as long. The disc is clothed in five rays of spines radiating from a spiny centre. Between these are five pairs of triangular plates, each pair forming a heart shaped pattern. The slender tapering arms are quite distinct from the disc and are covered with overlapping scales. The dorsal arm plates are naked and have a longitudinal keel. Each arm segment bears seven glassy, toothed spines. The arms are extremely fragile and easily shed, coming away either whole or in pieces.

This species is common around the coasts of Britain and Ireland and in the North Sea. It ranges southwards from the Lofoten Islands and Iceland to the Mediterranean Sea and the Azores, and along the west coast of Africa south to the Cape of Good Hope. It is most common on tide-swept rock and on coarse sediments, preferring hard substrates including sand and shingle. It is often found in empty shells or under stones, from the littoral zone down to 350 metres.