sp. nov., isolated from skin ulcers of sea-farmed fish, and description of sp. nov. with subdivision into genomovars and .

Results of previous multilocus sequence and whole-genome-based analyses have suggested that a homogeneous group of isolates belonging to the genus , represented by strain TNO020 and associated with skin ulcer development in sea-farmed fish, represents an as-yet-undescribed species. Comparative whole-genome analysis performed in the present study clustered five isolates, including TNO020, in a distinct lineage within the genus . Phenotypic differences, high intra-cluster average nucleotide identity (ANI) values and low ANI values with other species support the proposal of a novel species, for which we propose the name sp. nov. with strain TNO020 (=CCUG 73833=NCIMB 15240) as the type strain. Further, large-scale genome analyses confirmed the existence of two different phylogenetic lineages within '', a species effectively but not validly published previously. ANI values just above the species delineation threshold of 95-96 % confirmed that both lineages belong to the same species. This result was also supported by DNA-DNA hybridization values. Phenotypically, the two conspecific lineages are distinguishable by differences in growth temperature range and ability to degrade l-proline. For the group of isolates already commonly known as '', we propose the name sp. nov., with strain TNO006 (=CCUG 73831=NCIMB 15238) as the type strain. We further propose the subdivision of sp. nov. into two genomovars, genomovar with strain TNO006 (=CCUG 73831=NCIMB 15238) as the type strain and genomovar with strain TNO010 (=CCUG 73832=NCIMB 15239) as the type strain.