Since only one genus is currently recognized, the genus description corresponds to the family description.
Species demarcation criteria
Species demarcation criteria:
- Host of isolation
- Nucleotide and deduced amino acid sequence data (≤ 70% aa sequence identity in the RdRP)
- Number and length of dsRNA genome segments
- Presence of true capsid
Species demarcation considers a combination of each of the criteria listed above. While nucleotide and amino acid sequence relatedness are important criteria for species demarcation, the other listed criteria may be useful in the demarcation of “borderline cases”, e.g. when amino acid identities between the RdRPs is slightly above 70% but nevertheless the viruses belong to different species.