Asticcacaulis aquaticus sp. nov., Asticcacaulis currens sp. nov. and Asticcacaulis machinosus sp. nov., isolated from streams in PR China.

Three Gram-stain-negative, aerobic, rod-shaped, stalked and motile strains with a polar flagellum (BYS171W, DXS10W and LKC15W) were isolated from streams in PR China. Comparisons based on 16S rRNA gene sequences showed that strains BYS171W and DXS10W had the highest 16S rRNA gene sequence similarities (98.1 and 98.6 %, respectively) to CB 48, and strain LKC15W showed 99.6 % similarity to ZFGT-14. These three strains showed 16S rRNA gene sequence similarities of less than 96.9 % to other species of the genus . A phylogenetic tree reconstructed based on 16S rRNA gene sequences also showed that strains BYS171W and DXS10W took CB 48 as their closest neighbour, and strain LKC15W formed a tight cluster with ZFGT-14. The phylogenomic tree also showed that these three strains belong to the genus and form a distinct clade with the species of the genus . The major cellular fatty acids of these three strains were summed feature 3 (C 7 and/or C 6), summed feature 8 (C 7 and/or C 6), C and 11-methyl C 7. Their polar lipids mainly consisted of phosphatidylglycerol, unidentified glycolipids and nitrogen-containing phosphoglycolipids. The calculated OrthoANIu and digital DNA-DNA hybridization values among strains BYS171W, DXS10W, LKC15W and other related strains were less than 87.2 % and 34.0 %, respectively, indicating that these three strains should represent three independent novel species of the genus , for which the names sp. nov. (type strain BYS171W=GDMCC 1.3226=KCTC 92612), sp. nov. (type strain DXS10W=GDMCC 1.3224=KCTC 92543) and sp. nov. (type strain LKC15W=GDMCC 1.3225=KCTC 92544) are proposed.