A novel bacterium, designated strain CAU 1637T, was isolated from a tidal mudflat. Cells of strain CAU 1637T were Gram-stain-negative, aerobic, motile with single flagellum and rod-shaped. The optimum conditions for growth were observed at 30 °C, pH 6.0 and in the presence of 2 % (w/v) NaCl. The respiratory quinone was ubiquinone-10. Phylogenetic analysis based on 16S rRNA gene sequences showed that strain CAU 1637T was closely related to the genus
Roseibium
, with the highest similarity to
Roseibium aestuarii
NRBC 112946T (97.4 %), followed by
Roseibium hamelinense
NRBC 16783T (96.8 %),
Roseibium aquae
JCM 19310T (96.4 %),
Roseibium sediminis
KCTC 52373T (95.8 %) and
Roseibium denhamense
JCM 10543T (95.3 %). The predominant cellular fatty acids were C18 : 1
ω7c 11-methyl and summed feature 8 (C18 : 1
ω7c and/or C18 : 1
ω6c). The major polar lipids consisted of diphosphatidylglycerol and phosphatidylglycerol. The average nucleotide identity values between the novel isolate and related strains ranged from 71.0 to 76.4 %, and the DNA−DNA hybridization values ranged from 19.3 to 20.3 %. The G+C content was 58.4 mol% and the whole-genome size was 4.6 Mb, which included 17 contigs and 3931 protein-coding genes. Based on the taxonomic data, strain CAU 1637T represents a novel species of the genus
Roseibium
, for which the name Roseibium limicola sp. nov. is proposed. The type strain is CAU 1637T (=KCTC 82429T=MCCC 1K06080T).