A new species of eusirus from jeju island, Korea (Crustacea, Amphipoda, Eusiridae)

Abstract

A new eusirid amphipod, Eusirus bulbodigitus sp. N., from Jeju Island, Korea is described with a detailed description and illustrations. Eusirus bulbodigitus sp. n. shows common features with the five known eusirid amphipods E. abyssi Stephensen, 1944, E. columbianus Bousfield & Hendrycks, 1995, E. hirayamae Bousfield & Hendrycks, 1995, E. laticarpus Chevreux, 1906, and E. parvus Pirlot, 1934, such as the mandibular palp article 3 bearing a group of setae laterally. However, this new species is differentiated by the combination of the following characteristics: the eyes are poorly developed, the propodus on pereopod 4 is slightly shorter, the inner margin of dactylus on pereopod 4 is swollen, the length of pereopods 5-7 is moderate, the urosomite 1 has a dorsal protrusion distally, and the telson is shallowly cleft. This is the first record of the genus Eusirus Krøyer, 1845 from Korean waters.