On the presence of Prionospio pulchra (Polychaeta : Spionidae) in the Atlantic Ocean

The presence of the Japanese spionid polychaete Prionospio pulchra in the A tlantic Ocean is confirmed by specimens found in the north-west coast of Sp ain (Iberian Peninsula). This species is characterized by its eight to ten pairs of long and apinnate branchiae, the longest extending over six to eig ht segments, and by the presence of five prostomial marginal peaks. Notes o n variability of some anatomical aspects and ecological preferences of this species in the Atlantic coast of Spain are also given to complement the or iginal description.