Indo-West Pacific, North and Central Atlantic, and the Mediterranean. Cosmopolitan. Countries | FAO areas | Ecosystems | Occurrences | Introductions
Short description
Small ones: transparent and iridescent. Large one: pinkish red. Skin is smooth to small ones. Trunk: has no papillae; introvert is covered with triangular "scales" or large white papillae directed posteriorly. Some having 4 lobes - 2 dorsal and 2 ventral. Longitudinal muscle bands (LMBs): thick strong ridges; common 5-15 cm long with 24-34 LMBs. Refractors muscles are separate and attach at the same level, each with a broad base extending over 5 - 7 longitudinal muscle bands. Spindle muscle: attached anterior to the anus. Gut: attached to the body wall by several fixing muscles or connective tissue strands throughout its length; very thin, transparent, and fragile. Nephridia: vary in length; range from 10 to 20% of the trunk length. Nephridiopores: anterior to the anus between the 4th and 5th longitudinal muscle bands. Ventral nerve cord: loosely attached anteriorly with numerous, large, lateral offshoots to the introvert (Ref. 358).
Eulittoral; intertidal and subtidal on mud, rocks, sand, silt and in rock cracks or crevices (Ref. 358 and 1784). Occurs from 12 m (Ref. 358) in the littoral zone to 2275 m (Ref. 775) along continental shelf and slope (Ref. 1456). Predated on by the finfish Diplodus sargus sargus (Ref. 41986).
