Deep-sea Fauna and Pollutants off Pacifi c Coast of Northern Japan, edited by T. Fujita, National Museum of Nature and Science Monographs, No. 39, pp. 405-446, 2009 Deep-sea Mysidaceans (Crustacea: Lophogastrida and Mysida) from the North- western North Pacifi c off Japan, with Descriptions of Six New Species Kouki Fukuoka Ishigaki Tropical Station, Seikai National Fisheries Research Institute, Fisheries Research Agency, 148-446 Fukai-Ohta, Ishigaki, Okinawa, 907-0451 Japan E-mail:
[email protected] Abstract: Mysidaceans (Lophogastrida and Mysida) from deep waters off the northern Japan are reported. Four species of Lophogastrida and 33 species of Mysida were identifi ed. A new genus, Neoamblyops, and six new species, Ceratomysis japonica, C. orientalis, Holmesiella bisaetigera, Mysimenzies borealis, Neoambly- ops latisquamatus, and Paramblyops hamatilis, are described. Key words: Crustacea, Lophogastrida, Mysida, deep water, northern Japan, new genus, new species. Introduction Mysidaceans (Lophogastrida and Mysida) from deep waters off the Pacifi c coast of the north- ern Honshu, Japan, have been reported by W. Tattersall (1951), Birstein and Tchindonova (1958), Taniguchi (1969), Murano (1975, 1976), Fukuoka et al. (2005), and Fukuoka and Murano (2006). To date, two species of Lophogastrida and 11 species of Mysida have been recorded (Table 1). The present paper provides the taxonomic result of mysidacean specimens collected from deep waters off the northern Japan during a research project entitled “Research on Deep-sea Fauna and Pollutants off Pacifi c Coast of Northern Japan” as part of the “Study on Deep-Sea Fauna and Conservation of the Deep-Sea Ecosystem” conducted by the National Museum of Nature and Sci- ence, Tokyo.