Two bacterial strains (1-10M-8-7-50T and 1M) were isolated from lagoon sediments. The strains were obligately aerobic, Gram-stain-positive, spore-forming, rod-shaped and motile. Both strains were able to grow at 25-60 ˚C (optimum 40-42 ˚C), at pH 6.0-8.8 (optimum pH 7.0-7.5) and with 0-2.0 % (w/v) (optimum 0-0.8 %) NaCl. The predominant cellular fatty acids were iso-C15 : 0 and iso-C15 : 0 2-OH, and the cell-wall peptidoglycan contained meso-diaminopimelic acid, glutamic acid, glycine and alanine. Phosphatidyl-N-methylethanolamine, phosphatidylethanolamine, diphosphatidylglycerol, phosphatidylglycerol, two unidentified phosphoglycolipids and three unidentified lipids were present as polar lipids. Genomic DNA G+C content was 41.9 mol%. 16S rRNA gene sequence comparisons of both strains indicated that they belong to the genus Aneurinibacillus within the family Paenibacillaceae of the class Bacilli. Both strains had a sequence similarity of 97.6 % with Aneurinibacillus migulanus B0270T, 97.6 % with Aneurinibacillus aneurinilyticus ATCC 12856T, 97.5 % with 'Aneurinibacillus humi' U33 and <97 % with other members of the genus Aneurinibacillus. The DNA-DNA reassociation value between strain 1-10M-8-7-50T and 1M was >90 %, while strains 1-10M-8-7-50T and 1M were only 35.1±1, 29.8±1 and 24.5±1 % related to A. migulanus KACC 18173T, A. aneurinilyticus KACC 18174T and 'A. humi' U33, respectively. Distinct morphological, physiological and genotypic differences from the previously described taxa support the classification of strain 1-10M-8-7-50T as a representative of a novel species in the genus Aneurinibacillus, for which the name Aneurinibacillus sediminis sp. nov. is proposed. The type strain is 1-10M-8-7-50T (=KEMB 563-460T=JCM 31819T).