Members of the species Agrobacterium ferrugineum were isolated from marine environments. The type strain of this species (= LMG 22047(T) = ATCC 25652(T)) was recently reclassified in the new genus Pseudorhodobacter, in the order 'Rhodobacterales' of the class 'Alphaproteobacteria'. Strain LMG 128 (= ATCC 25654) was also initially classified as belonging to the species Agrobacterium ferrugineum; however, the nearly complete 16S rRNA gene sequence of this strain indicated that it does not belong within the genus Agrobacterium or within the genus Pseudorhodobacter. The closest related organism, with 95.5 % 16S rRNA gene similarity, was Aquamicrobium defluvii from the family 'Phyllobacteriaceae' in the order 'Rhizobiales'. The remaining genera from this order had 16S rRNA gene sequence similarities that were lower than 95.1 % with respect to strain LMG 128. These phylogenetic distances suggested that strain LMG 128 belonged to a different genus. The major fatty acid present in strain LMG 128 was mono-unsaturated straight chain 18 : 1omega7c. The G + C content of the DNA was 53.1 mol%. Strain LMG 128 grew at 4 degrees C but not at 40 degrees C, and tolerated up to 5 % NaCl. The pH range for growth was 6-8. It produced urease and beta-galactosidase, and hydrolysed aesculin. Denitrification was negative. Growth was observed with many carbohydrates as the only carbon source. The data from this polyphasic study indicate that this strain belongs to a new genus of the family 'Phyllobacteriaceae', and therefore it is proposed that strain LMG 128(T) should be reclassified as representing a novel species within the new genus Hoeflea gen. nov., for which the name Hoeflea marina sp. nov. is proposed.