The Gram-stain-negative, orange-pigmented, non-spore-forming, non-motile, strictly aerobic, rod-shaped bacterial strain, designated TP-CH-4T, was isolated from a seamount near the Yap Trench in the tropical western Pacific. The optimal growth conditions were determined to be at pH 7–8, 25–30 °C and in the presence of 2 % (w/v) NaCl. The major respiratory quinone was MK-6. The polar lipid profile contained phosphatidylethanolamine, two unidentified aminolipids, two unidentified phospholipids and three unidentified polar lipids. The predominant cellular fatty acids were iso-C15 : 0 and summed feature 1 (composed of C13 : 03-OH and/or iso-C15 : 1H). Phylogenetic analysis of 16S rRNA gene sequences revealed that strain TP-CH-4T was a member of the family
Flavobacteriaceae
and formed a distinct lineage. Strain TP-CH-4T displayed highest sequence similarities to
Pseudozobellia thermophila
KMM 3531T (95.1 %) and
Flagellimonas flava
A11T (93.9 %). Genome sequencing revealed the strain TP-CH-4T has a genome size of 4.5 Mbp and a G+C content of 44.5 mol%. Collectively, based on phenotypic, chemotaxonomic, phylogenetic and genomic evidence, strain TP-CH-4T represents a novel species of a novel genus of the family
Flavobacteriaceae
, for which the name Pelagihabitans pacificus gen. nov., sp. nov. is proposed. The type strain of Pelagihabitans pacificus is TP-CH-4T (=CGMCC 1.17120T=KCTC 72434T).