Haloferax (common abbreviation: Hfx.) is a genus of halobacteria in the order Haloferacaceae.

Genetic exchange

Cells of H. mediterranei and cells of the related species H. volcanii can undergo a process of genetic exchange between two cells which involves cell fusion resulting in a heterodiploid cell (containing two different chromosomes in one cell). Although this genetic exchange ordinarily occurs between two cells of the same species, it can also occur at a lower frequency between an H. mediterranei and an H. volcani cell. These two species have an average nucleotide sequence identity of 86.6%. During this exchange process, a diploid cell is formed that contains the full genetic repertoire of both parental cells, and genetic recombination is facilitated. Subsequently, the cells separate, giving rise to recombinant cells.

Taxonomy

As of 2022, 13 species are validly published under the genus Haloferax. Several species and novel binomial names have been proposed, but not validly published.

Phylogeny

The currently accepted taxonomy is based on the List of Prokaryotic names with Standing in Nomenclature (LPSN) and National Center for Biotechnology Information (NCBI).