Family: Cystoviridae
Genus: Cystovirus
Distinguishing features
Since only one genus is currently recognized, the genus description corresponds to the family description.
Species demarcation criteria
Species are demarcated based upon nucleotide sequence distances for the L, M and S segments being greater than 0.05 for comparisons between members of different species; nucleotide sequence distances are > 0.35 for comparisons between members of all species except for Cystovirus phi6 and Cystovirus phiNN, for which distances are > 0.15 (Figure 4.Cystoviridae).