Ophiuridae

Ophiuridae are a large family of brittle stars of the suborder Ophiurina.

Description

The arms are simple and unbranched, projecting from and well-fused to the edge of the disc. These arms move horizontally. The arm spines short and movable. They lie flat against the arms when stimulated, but held erect when the brittle star is at rest. Disc and arms are covered in naked, distinct scales. The scales are situated at both sides of the disc.

The jaw is surrounded by a continuous series of mouth papillae. The base of the arm contains a single arm comb or an inner and outer arm comb.

Systematics and phylogeny

The fossils of Ophiuridae date back to Carboniferous (Aganaster†). The family includes the following living genera: