The subfamily Letovirinae was established for Microhyla letovirus 1 (Figure 1.Letovirinae) based on DEmARC analysis of the nidovirus-wide conserved 3CLpro, NiRAN, RdRP, ZBH and HEL1 domains.
Figure 1.Letovirinae. Letovirus genome organization. 3′-terminal ORFs downstream of ORF1b are depicted as coloured boxes with red, S; cyan, E; yellow, M and magenta, N. ORFs for accessory proteins are depicted as coloured boxes in grey.
Genus demarcation criteria
There is only one genus in the subfamily. Details correspond to the family descriptions.