Five strains (Ryu1-2(T), Gon2-9, Ryu4-3, Nog8-1 and Aza1-1) of lactic acid bacteria were isolated from flowers in mountainous areas in Japan, Oze National Park, Iizuna mountain and the Nikko area. The five isolates were found to share almost identical (99.6-100 % similar) 16S rRNA gene sequences and were therefore deemed to belong to the same species. These isolates exhibited low levels of 16S rRNA gene sequence similarity to known lactic acid bacteria; the closest recognized relatives to strain Ryu1-2(T) were the type strains of Lactobacillus hilgardii (92.8 % similarity), Lactobacillus kefiri (92.7 %), Lactobacillus composti (92.6 %) and Lactobacillus buchneri (92.4 %). Comparative analyses of rpoA and pheS gene sequences demonstrated that the novel isolates did not show significant relationships to other Lactobacillus species. The strains were Gram-stain-positive, catalase-negative and homofermentative. The isolates utilized a narrow range of carbohydrates as sources of carbon and energy, including glucose and fructose. On the basis of phenotypic characteristics and phylogenetic data, these isolates represent a novel species of the genus Lactobacillus, for which the name Lactobacillus floricola sp. nov. is proposed. The type strain is Ryu1-2(T) (= NRIC 0774(T) = JCM 16512(T) = DSM 23037(T)).