Two strains, designated DW5-4T and NH7I_1T, were isolated from aquaculture water of a shrimp farm of Zhangzhou city in China and from surface sediment of the South China Sea, respectively. Cells of the strains were Gram-stain-positive, oxidase- and catalase-positive, rod-shaped and motile. Phylogenetic analyses based on 16S rRNA gene sequences indicated that the two strains belonged to the Bacillus pumilus clade. 16S rRNA gene sequence similarity between strains DW5-4T and NH7I_1T was 99.8 %, and between each of the two strains and four type strains, B. pumilus ATCC 7061T, Bacillus safensis FO-36bT, Bacillus altitudinis 41KF2bT and Bacillus xiamenensis HYC-10T, were above 99.4 %. The digital DNA-DNA hybridization value between the two novel strains was 41.6 %, and between each of the two strains and the four above-mentioned type strains were below 53.0 %. In both strains, the principal fatty acids were iso-C15 : 0 and anteiso-C15 : 0, and the isoprenoid quinone was identified as MK-7 (100 %). The DNA G+C contents of strains DW5-4T and NH7I_1T were 41.4 and 41.3 mol%, respectively. Based on phenotypic and genotypic characteristics, two novel species of the genus Bacillus are proposed: Bacillus zhangzhouensis sp. nov., with DW5-4T ( = MCCC 1A08372T = LMG 27144T = KCTC 33531T) as the type strain, and Bacillus australimaris sp. nov., with NH7I_1T ( = MCCC 1A05787T = LMG 27697T = KCTC 33532T) as the type strain.