Description of Kushneria aurantia gen. nov., sp. nov., a novel member of the family Halomonadaceae, and a proposal for reclassification of Halomonas marisflavi as Kushneria marisflavi comb. nov., of Halomonas indalinina as Kushneria indalinina comb. nov. and of Halomonas avicenniae as Kushneria avicenniae comb. nov

1 Department of Microbiology and Parasitology, Faculty of Pharmacy, University of Sevilla, 41012 Sevilla, Spain 2 Biology Department, Box 9012, University of Puerto Rico, Mayagüez 00681, Puerto Rico Correspondence Antonio Ventosa ventosa{at}us.es An aerobic, moderately halophilic, Gram-negative, motile, non-sporulating rod-shaped bacterium, designated strain A10 T , was isolated from the surface of leaves of the black mangrove Avicennia germinans and was subjected to a polyphasic taxonomic study. Strain A10 T was able to grow at NaCl concentrations in the range 5–17.5 % (w/v) with optimum growth at 10 % (w/v) NaCl. Growth occurred at temperatures of 20–40 °C (optimal growth at 37 °C) and pH 5.5–8.5 (optimal growth at pH 7.0–8.0). The major respiratory quinone was ubiquinone 9. The major fatty acids were C 16 : 0 , C 18 : 1 7 c , C 19 : 0 cyclo 8 c and C 12 : 0 3-OH. The polar lipids were phosphatidylglycerol, diphosphatidylglycerol, phosphatidylethanolamine, and unidentified phospholipids, glycolipids and an aminoglycolipid. Phylogenetic analysis based on 16S rRNA gene sequence comparisons revealed that strain A10 T is closely related to Halomonas avicenniae MW2a T (95.7 % sequence similarity), Halomonas marisflavi SW32 T (95.2 %) and Halomonas indalinina GC2.1 T (95.0 %). Strain A10 T formed a coherent phylogenetic branch with these three species, separated from other species of Halomonas and closely related genera (with 16S rRNA gene sequence similarities below 94.0 %). A complete 23S rRNA gene sequence comparison of strain A10 T with closely related species confirmed the phylogenetic position of the novel isolate, forming a branch with the species Halomonas avicenniae, Halomonas indalinina and Halomonas marisflavi , separated from other species of the genera belonging to the family Halomonadaceae (showing sequence similarities below 91.7 %). DNA–DNA hybridization studies between strain A10 T and Halomonas avicenniae MW2a T , Halomonas marisflavi DSM 15357 T and Halomonas indalinina CG2.1 T were 21, 17 and 10 %, respectively. These levels of DNA–DNA relatedness were low enough to classify strain A10 T as representing a genotypically distinct species. Overall, the phenotypic, genotypic, chemotaxonomic and phylogenetic results demonstrated that strain A10 T represents a new genus and species. The name Kushneria aurantia gen. nov., sp. nov. is proposed, with strain A10 T (=CCM 7415 T =CECT 7220 T ) as the type strain. This is the type species of the new pro