One new species of Krøyer, 1842 (Amphipoda, Stegocephalidae) described from a seamount of the Caroline Plate, NW Pacific.

A new species of the subfamily Stegocephalinae, , is described from a seamount in the Caroline Plate. Two related species, (Moore, 1992) and (Gurjanova, 1962), were previously reported in the North Pacific. Important morphological characters which differentiate from are found in antenna 1, the mouthparts, pereopod 7 and the length of rami of uropods 2 and 3.

A new species of (Amphipoda, Tryphosidae) described from hydrothermal vent in the Okinawa Trough, Northwest Pacific.

A new species of the family Tryphosidae, , is described from hydrothermal vents in the Okinawa Trough. This is the first known species found in vent fields. Important morphological characters that differentiate from its congeners are the absence of eyes, the compressed distal three articles of gnathopod 2, the shape of the posterior margin of epimerons 2 and 3, and the number of dorsal spines on the telson.

sp. nov., a new calcified amphipod (Amphipoda, Amphilochidea, Epimeriidae) from a seamount of the Caroline Plate, NW Pacific.

A calcified individual of Costa, 1851 collected from an unnamed seamount of the Caroline Plate, NW Pacific, is recognized as new to science herein. This increases the number of known species of the North Pacific to nine. differs from its similar congeners by having a rostrum hardly reaching to the end margin of first peduncular article of antenna 1, the presence of large pyriform eyes, the size-increasing mid-dorsal teeth starting from pereonite 6 to pleonite 2, the projection on coxa 5 not extending to epimeral plate 1, and by having a nearly quadrate telson notched medially.

Description of sp. nov. from hydrothermal vents in the Okinawa Trough, Northwest Pacific (Amphipoda, Amphilochoidea, Sebidae).

, of the family Sebidae Walker, 1908, is described from hydrothermal vents in Okinawa Trough. Other two congenic species, Larsen, 2007 and Shaw, 1989, are also reported from these hydrothermal vents, but the new species can be readily distinguished from them in having the merus of pereopods 5 and 6 extending beyond distal margin of carpus, coxa 4 smaller than coxae 2 and 3, and coxa 5 with the posterior lobe larger than the anterior one, rather than equilobate.

Probathylepadidae, a new family of Scalpelliformes (Thoracica: Cirripedia: Crustacea), for Probathylepas faxian gen. nov., sp. nov., from a hydrothermal vent in the Okinawa Trough.

A new pedunculate barnacle, Probathylepas faxian gen. and sp. nov.

A new species of Sinocorophium from the Yangtze estuary (Crustacea: Amphipoda: Corophiidae: Corophiinae: Corophiini), China.

Amphipods collected from the Yangtze estuary, Shanghai, China are described as a new species, Sinocorophium dongtanense. It is closely allied to Sinocorophium homoceratum Yu, 1938 but differs markedly in the inner lateral side of peduncular article 4 of male antenna 2 having two rows of teeth.

Two new species and one newly recorded species of the genus Kamaka (Crustacea: Amphipoda) from the Hainan Province, South China Sea.

A total of 5 species of the genus Kamaka (Crustacea: Amphipoda) are identified from Hainan Province, South China Sea. In those, one species, Kamaka excavata Ariyama, 2007, is recorded for the first time in Chinese waters. Two new species, Kamaka corophina sp.