About Echinaster sepositus (Retzius, 1783)
Echinaster sepositus has five relatively slender arms surrounding a small central disc. It usually reaches an overall diameter of up to 20 cm (8 in), and may exceptionally grow as large as 30 cm (12 in) across. This species is bright orange-red in color, with a soapy surface texture that distinguishes it from the superficially similar Henricia starfish. Another species that is somewhat similar and shares the same region is Ophidiaster ophidianus. The surface of Echinaster sepositus is dotted with evenly spaced pits; from these pits, the animal can extend its deep red gills, called papulae.
Echinaster sepositus occurs in the East Atlantic Ocean north of the Equator, including the Mediterranean Sea, where it is one of the most common starfish species, though it is virtually absent from some localities. Its northern range limit is the English Channel, and it occurs there only on the French side of the channel. It can be found at depths between 1 m and 250 m (3 ft to 820 ft), and lives in a wide variety of habitats. These habitats include rocky, sandy, and muddy bottoms, as well as sea grass meadows of Posidonia oceanica and Zostera.
