Astacilla boreaphilis sp nov (Crustacea : Isopoda : Valvifera) from shallow and deep North Atlantic waters

Astacilla boreaphilis sp. nov. is described from shallow and deep waters off Iceland and Greenland. A. boreaphilis sp. nov. is easily distinguished from all but one of the Astacilla species recorded from the North Atlantic by the absence of eyes and from all other Astacilla species by the pattern of the spines on the body. The species shows pronounced sexual dimorphism. The species occurs at depths between 219 and 1809 m and at temperatures between 2.4 degrees C and 7.2 degrees C. The species is therefore restricted to Atlantic Water (AW), characterizing the area south of the Greenland - Iceland - F roe Ridge and to Atlantic Water presumably diluted by cold water masses from the Nordic Seas. The depth range in the area differs locally and may be limited by cold water currents crossing the Ridge.