Two halophilic archaeal strains, R30T and tADLT, were isolated from an aquaculture farm in Dailing, China, and from Deep Lake, Antarctica, respectively. Both have rod-shaped cells that lyse in distilled water, stain Gram-negative and form red-pigmented colonies. They are neutrophilic, require >120 g/l NaCl and 48'67 g/l MgCl2 for growth but differ in their optimum growth temperatures (30 °C, tADLT vs. 40 °C, R30T). The major polar lipids were typical for members of the Archaea but also included a major glycolipid chromatographically identical to sulfated mannosyl glucosyl diether (S-DGD-1). The 16S rRNA gene sequences of the two strains are 97.4 % identical, show most similarity to genes of the family Halobacteriaceae, and cluster together as a distinct clade in phylogenetic tree reconstructions. The rpoB' gene similarity between strains R30T and tADLT is 92.9 % and less to other halobacteria. Their DNA G + C contents are 62.4'62.9 mol % but DNA'DNA hybridization gives a relatedness of only 44 %. Based on phenotypic, chemotaxonomic and phylogenetic properties, we describe two new species of a novel genus, represented by strain R30T (= CGMCC 1.10593T = JCM 17270T) and strain tADLT (= JCM 15066T = DSMZ 22187T) for which we propose the names Halohasta litorea gen. nov., sp. nov. and Halohasta litchfieldiae sp. nov., respectively.