Paper Title
Species Diversity and Phylogenetic Relationships of Symbiotic Crustaceans on Portunus Pelagicus (Linneus 1758) in Vietnam

Abstract
Blue swimming crab (Portunus pelagicus) was the economic and ecological important species in Vietnam, and potential subject for aquaculture as well. More than 400 crab individuals were collected along the Vietnamese coastline, and examined for ectosymbiotic crustacean. High diversity of 7 species have been reported, and 7 probably new for science. The significant differences were detected between the infestation status of common occurring symbionts against the crab host distribution (north, cemter, and south), sexes, and size groups. Symbiotic crustacean occupied specific niche(s) on crab body. Molecular phylogeny supported the separation of 2 distinct lineages represented for two subclass (Thecostraca and Copepoda. Further studies need to be conducted for new species description. Keywords - Symbionts, Crustacean, Portunus pelagicus, Phylogeny, Infection, Vietnam