Microvirga terricola sp. nov. and Microvirga solisilvae sp. nov, isolated from forest soil

Two Gram-staining-negative, aerobic and rod-shaped strains, designated c23x22T and sex2T, were isolated from forest soil collected from Chebaling National Nature Reserve in Guangdong Province and Limu Mountain National Forest Park in Hainan Province, P. R. China, respectively. Phylogenetic analyses based on 16S rRNA gene sequences revealed that they belonged to the genus Microvirga, and strain c23 x22T was most closely related to ‘Microvirga alba’ KCTC 72385, while strain sex2T showed close relationship with Microvirga guangxiensis CGMCC 1.7666T. The average nucleotide identity and digital DNA–DNA hybridization values between strains c23 x22T and sex2T and their close relatives, ‘M. alba’ KCTC 72385 and M. guangxiensis CGMCC 1.7666T, were all below the threshold values for species delimitation. The predominant quinones of the two novel strains were ubiquinone 10, and the major fatty acids contained C19:0 cyclo ω8c and summed feature 8 (C18:1ω7c and/or C18:1ω6c). Their predominant polar lipids were phosphatidylglycerol, diphosphatidylglycerol, phosphatidylethanolamine and phosphatidylcholine. The phenotypic, genotypic and chemotaxonomic analyses clearly supported that strains c23 x 22T and sex2T represent two novel species of the genus Microvirga, for which the name Microvirga terricola sp. nov. (type strain c23 x 22T = GDMCC 1.1700T = KCTC 62432T) and Microvirga solisilvae sp. nov. (type strain sex2T = GDMCC 1.1651T = KACC 21311T) are proposed, respectively.