Hanstruepera neustonica gen. nov., sp. nov., a zeaxanthin-producing member of the family Flavobacteriaceae isolated from estuarine water, and emendation of Sediminibacter furfurosus Khan et al. 2007 emend. Kwon et al. 2014, Mangrovimonas yunxiaonensis Li et al. 2013, Antarcticimonas flava Yang et al. 2009 and Hoppeia youngheungensis Kwon et al. 2014.

A Gram-staining-negative, strictly aerobic, yellowish-orange, flexirubin-positive, rod-shaped, non-flagellated, non-spore-forming and non-gliding marine bacterium, designated strain CC-PY-50(T), was isolated from estuarine water off Pingtung, Taiwan. The strain produced zeaxanthin as a major carotenoid pigment, and showed highest pairwise 16S rRNA gene sequence similarity to Bizionia hallyeonensis T-y7(T) (93.9 %) followed by Corallibacter vietnamensis KMM 6217(T) (93.8 %), Geojedonia litorea YCS-16(T) (93.7 %) and other members of the family Flavobacteriaceae (<93.7 %). Strain CC-PY-50(T) established a distinct phyletic lineage associated with Mangrovimonas yunxiaonensis LYYY01(T) (93.1 % sequence similarity) with poor bootstrap support during neighbour-joining and maximum-likelihood phylogenetic analyses (37 % for each). The polar lipid profile of strain CC-PY-50(T) was determined to accommodate large numbers of unknown lipids including major amounts of three unidentified aminolipids and two unidentified lipids, and moderate amounts of an unidentified phospholipid, an unidentified glycolipid and an unidentified lipid. In addition, phosphatidylethanolamine was also detected in significant amounts. The major (>5 % of total) fatty acids were iso-C15 : 0, iso-C15 : 1 G, iso-C17 : 0 3-OH, C16 : 0 and C16 : 1ω6c and/or C16 : 1ω7c. The DNA G+C content was 37.1 mol% and menaquinone-6 (MK-6) was the sole respiratory quinone. Based on the phylogenetic evidence and several distinguishing phenotypic and chemotaxonomic features, strain CC-PY-50(T) is proposed to represent a novel genus and species of the family Flavobacteriaceae, for which the name Hanstruepera neustonica gen. nov., sp. nov. is proposed. The type strain of the type species Hanstruepera neustonica gen. nov., sp. nov. is CC-PY-50(T) ( = JCM 19743(T) = BCRC 80747(T)). Emended descriptions of the species Sediminibacter furfurosus, Mangrovimonas yunxiaonensis, Antarcticimonas flava and Hoppeia youngheungensis are also proposed.