RNA viruses belonging to the phylum Duplornaviricota are characterized by homologous RNA-dependent-RNA polymerases, typically classified within the PFAM RdRp_4 or RdRp_5 families. These viruses possess double-stranded RNA genomes and major capsid proteins exhibiting a BTV-like fold. Their capsids are icosahedral with a T=2* symmetry. Members of the orders Reovirales and Mindivirales additionally feature an outer capsid layer with a T=13 symmetry.