Ten Species of Pisione (Annelida : Polychaeta : Pisionidae) from Japan and Evolutionary Trends in the Genus Based on Comparison of Male Copulatory Apparatus

Abstract

Five new species and three new subspecies of the genus Pisione are described based on material from Japan. In addition, P. parva, newly recorded from Japan, and P. africana, once recorded from Japan without description, are described. Results of SEM observations, especially on their male copulatory apparatus, are presented. Japanese fauna with as many as 14 species is summarized. Male copulatory apparatus in the whole genus are compared, and four groups of closely related species are recognized. Their phylogenetic relationships and evolutionary trends are discussed.