Discovery of two novel totiviruses from Culex tritaeniorhynchus classifiable in a distinct clade with arthropod-infecting viruses within the family Totiviridae

Two double-stranded RNA viruses, named Culex tritaeniorhynchus totivirus NJ2 (CTV_NJ2) and NJ3 (CTV_NJ3), were discovered from wild-captured Culex tritaeniorhynchus mosquitoes. The complete genomes (7,624 and 7,612 bp in length) were obtained using RNA sequencing. Both CTV_NJ2 and CTV_NJ3 encode a putative capsid protein and an RNA-dependent RNA polymerase. The most similar strain to CTV_NJ2/3 is Omono River virus strain AK4 (ORV-AK4). The CP and RdRp identities of AK4 are different to CTV_NJ2 (84% and 87%) and CTV_NJ3 (47% and 62%). Phylogenetic analysis showed that taxonomically speaking CTV_NJ2/3 grouped within the unclassified Totiviridae and formed a distinct clade with other arthropod-infecting viruses.