INTERSTITIAL POLYCHAETES OF JAPAN. III. SIX SPECIES OF MICROPHTHALMINAE (HESIONIDAE) INCLUDING A NEW SPECIES AND THREE NEW SUBSPECIES

Abstract

The genera Hesionides and Microphthalmus of the family Hesionidae are known to be regular components of the interstitial polychaete fauna of marine sandy beaches. The former is known to contain nine species, all of which are purely interstitial forms; the latter is composed of nineteen species, most of which are also known to be typical interstitial inhabitants. In the west coast of North Pacific, however, only H. arenaria has been recorded from Japan (Sudzuki, 1976; Westheide, 1977a). In the course of the author's recent research on the interstitial polychaetes along Japanese coasts, he obtained a number of specimens of both genera from various localities. As a result of this research, the present paper reports five species of Hesionides including a new species and two new subspecies, and one species of Microphthalmus which is a new subspecies.