Periclimenes cannaphilus, new species, the second palaemonid shrimp (Crustacea: Decapoda: Caridea) associated with sibogrinid tube worm inhabiting hydrothermal vents

A new species of the palaemonid shrimp genusPericlimenes, P. cannaphilus, is described from upper bathyal hydrothermal vents of the Bonin-Mariana Arc in the north-western Pacific at depths of 392–456 m. A symbiotic relationship between the new shrimp species and a siboglinid tube wormLamellibrachia satsumais suggested by their simultaenuous collection and further observationsin situ. Similarities in the morphology and symbiotic association suggest that the new species is closely related toP. thermohydrophilus, also associated withL. satsumain shallow hydrothermal vent fields in Kagoshima Bay, southern Japan, but differences in the rostral shape, the position of the epigastric tooth on the carapace, and the development of the hepatic tooth on the carapace morphologically differentiate the two species. Phylogenetic analysis based on sequences of the mitochondrial DNA COI gene supports the recognition of two clades corresponding to these two taxa.