High-resolution characterization of gill symbiont diversity of alvinocaridid shrimps in different chemosynthetic ecological niches using full-length 16S rRNA gene amplicon sequencing

Shrimps of the family Alvinocarididae with ectosymbionts in gills are endemic species to deep sea chemosynthetic ecosystems. Among them, Alvinocaris longirostris and Shinkaicaris leurokolos occupy different ecological niches within the same hydrothermal vent in Okinawa Trough, of which A. longirostris inhabits on mussel beds surrounding the base of hydrothermal vents (ALHV), while S. leurokolos lives tightly close to the vent (SLHV). In addition, A. longirostris also exists in a methane seep of the South China Sea (ALMS). In this study, full-length 16S rRNA sequences of the gill symbionts of two alvinocaridid species from different chemosynthetically ecological niches were first captured by single-molecule real-time sequencing