IMIS

This chapter provides a brief taxonomic conspectus of the Japanese nemerteans with photographs of 100 species. A total of 126 species are recognized in Japanese waters, but there are still at least 77 unreported/undescribed forms awaiting formal description. Previous records of 4 species (Amphiporus gelatinosus Coe, 1905; Cerebratulus longiceps Coe, 1901; Cerebratulus montgomeryi Coe, 1901; and Emplectonema buergeri Coe, 1901) are regarded to be unsubstantiated. The names of the 3 species Cerebratulus penniger Iwata, 1957, Euborlasia proteres Iwata, 1957, and Lineus nipponensis Senz, 2001 are treated as nomina dubia. The following 6 are herein judged as junior synonyms of older names: Amphiporus insolitus Iwata, 1954 [=Diplomma serpentina (Stimpson, 1855)]; Amphiporus reduncus Iwata, 1957 and Amphiporus retrotumidus Iwata, 1957 [=Nipponnemertes ogumai (Yamaoka, 1947)]; Cerebratulus albocirculus Iwata, 1957 [=Lineus albovittatus (Stimpson, 1855)]; Cerebratulus fasciatus Stimpson, 1857 [=Notospermus geniculatus (Delle Chiaje, 1828)]; and Tetrastemma yamaokai Iwata, 1954 [=Tetrastemma roseocephalum (Yamaoka, 1947)]. Five species are herein added as new members of the Japanese nemertean fauna: Cerebratulus rubellus (Stimpson, 1855); Cerebratulus signatus Coe, 1905; Micrura callima Sundberg and Gibson, 1995; Tetrastemma pimaculatum Chernyshev, 1998; and Tortus tokmakovae Chernyshev, 1991.