A 2021 taxonomy update for the family Smacoviridae

The family Smacoviridae (order Cremevirales, class Arfiviricetes, phylum Cressdnaviricota) is comprised of viruses with small circular single-stranded DNA genomes of ~2.3-3 kb in length that have primarily been identified in fecal sample of various animals. Smacovirus genomes carry two genes in ambisense orientation encoding a capsid protein and a rolling-circle replication initiation protein, respectively. We have revised the taxonomy of the family by assigning 138 new genomic sequences deposited in GenBank to already established taxa as well as 41 new species and six new genera. Furthermore, we have adopted binomial species nomenclature, conforming to the “Genus + freeform epithet” format for all 84 species from 12 genera. The updated Smacoviridae taxonomy presented in this article has been ratified by the International Committee on Taxonomy of Viruses (ICTV).