A light-yellow-coloured bacterium, designated strain PTJT-5(T), was isolated from the stem of Smilacina japonica A. Gray collected from Taibai Mountain in Shaanxi Province, north-west China, and was subjected to a taxonomic study by using a polyphasic approach. The novel isolate grew optimally at 25-28 °C and pH 6.0-7.0. Flexirubin-type pigments were produced. Cells were Gram-reaction-negative, strictly aerobic, rod-shaped and non-motile. Phylogenetic analysis based on 16S rRNA gene sequences showed that strain PTJT-5(T) was a member of the phylum Bacteroidetes, exhibiting the highest sequence similarity to Lacibacter cauensis NJ-8(T) (87.7 %). The major cellular fatty acids were iso-C15 : 0, iso-C15 : 1 G, iso-C17 : 0 and iso-C17 : 0 3-OH. The only polyamine was homospermidine and the major polar lipid was phosphatidylethanolamine. The only respiratory quinone was MK-7 and the DNA G+C content was 40.3 mol%. Based on the phenotypic, phylogenetic and genotypic data, strain PTJT-5(T) is considered to represent a novel species of a new genus in the family Chitinophagaceae, for which the name Taibaiella smilacinae gen. nov., sp. nov. is proposed. The type strain of Taibaiella smilacinae is PTJT-5(T) ( = CCTCC AB 2013017(T) = KCTC 32316(T)). An emended description of Flavihumibacter petaseus is also proposed.