Five Gram-negative bacterial isolates, recovered from an outbreak that occurred in March 2006 in Huelva, Spain, affecting adult diseased cultured wedge sole [Dicologlossacuneata(Moreau)], were characterized phenotypically and genotypically in order to clarify their taxonomic position. On the basis of 16S rRNA gene sequence analysis, the isolates were included in the genus Pseudomonas , within the Pseudomonas fluorescens -related species group, their closest relatives being the Pseudomonas jessenii and Pseudomonas koreensis subgroups. The highest sequence similarities were recorded with the type strains of Pseudomonas reinekei , P. moorei , P. umsongensis , P. jessenii and P. mohnii (99.4–99.3 % similarity). Sequence analysis of the housekeeping genesgyrBandrpoDclearly differentiated the isolates from currently described Pseudomonas species, the highest sequence similarities recorded to type strains being below 95 % for both genes. Phylogenetic analysis using concatenated sequences of the three genes showed Pseudomonas moraviensis DSM 16007^Tand P. koreensis DSM 16610^Tas the closest reference strains. DNA–DNA hybridization assays with related strains confirmed that these isolates belong to a novel species of the genus Pseudomonas , for which the namePseudomonas baeticasp. nov. is proposed. The type strain is strain a390^T( = CECT 7720^T = LMG 25716^T). The novel species could be easily distinguished from phylogenetically related species by several phenotypic characteristics, including gelatin hydrolysis, acid production from glucose and growth at 6 % NaCl. Virulence assays revealed that the novel species is pathogenic for wedge sole.