Caridea; Periclimenes laevimanus; new species; South China Sea; symbiosis; hydroid-associate

A new, hydroid-associated representative of the genus Periclimenes from Vietnam is described and illustrated. Periclimenes laevimanus, sp. nov. is most similar to P. granulimanus Bruce, 1978, but differs from it by more slender and smooth, not granulated, major second pereiopod, and toothless cutting edges of the minor second pereiopod. A key for identification of species of the newly established P. granulimanus species group is provided. Types or museum specimens of some other Periclimenes species (P. hongkongensis Bruce, 1969, P. nomadophila Berggren, 1994, P. ruber Bruce, 1982, and P. toloensis Bruce, 1969) were examined to evaluate their relation to P. granulimanus species complex.