Published online by Cambridge University Press: 31 May 2012
A comprehensive review of the literature on shallow-water asteroids (Echinodermata) recorded in Azores was carried out to establish a definitive list for the Archipelago. A total of 49 echinoderm species was compiled, comprising members of all extant classes; Crinoidea (1), Asteroidea (12), Ophiuroidea (11), Echinoidea (10) and Holothuroidea (7). References of asteroids occurence in the Azores, including historical records and distribution of asteroids from the Azores are given. Seven asteroid species recorded found in the Azores are found also in the Mediterranean and adjoining Atlantic coastlines, three are recorded from the Mediterranean and both sides of the Atlantic, one is limited to the Eastern Atlantic and one is circumtropical. Differences between the littoral hydrological conditions found on the North American coast and those in Azores makes the colonization from American coasts particularly difficult and probably are related to chance events like the episodic anomalies found in the general pattern of oceanic circulation. Asteroids are important in determining habitat structure for other species and can represent a substantial portion of the ecosystem biomass.