halorhabdus halorhabdus halorhabdus is a genus of halophilic archaea in the haloarculaceae. with an extremely high salinity optimum of 27% nacl, halorhabdus has one of the highest reported salinity optima of any living organism. halorhabdus scientific classification domain: archaea kingdom: euryarchaeota phylum: euryarchaeota class: halobacteria order: halobacteriales family: haloarculaceae genus: halorhabduswainø et al. 2000 emend. antunes et al. 2008 species h. amylolytica h. rudnickae h. salina h. tiamatea h. utahensis (type sp.)