Technical Abstract: Raspberry latent virus (RpLV) is a newly characterized reovirus found in commercial raspberry fields in the Pacific Northwest (PNW). Phylogenetic analyses showed that RpLV is related most closely to Rice ragged stunt virus (RRSV), the type member of the genus Oryzavirus. However, the conserved nucleotide termini of the genomic segments of RpLV did not match those of RRSV or other plant reoviruses, suggesting that RpLV is a possible member of a new genus in the Reoviridae. Thus far, all members of the plant reoviruses are transmitted in a replicative persistent manner by several species of leafhoppers or planthoppers. After several failed attempts to transmit RpLV using leafhoppers found on raspberry plants, Amphorophora agathonica Hottes, the large raspberry aphid commonly found in the PNW, was tested as a vector of the virus. Few plants tested positive for the virus when inoculated with groups of 50 viruliferous aphids, suggesting that aphids are inefficient vectors of RpLV. Using absolute and relative quantification methods, it was shown that the virus titer in aphids continued to increase after the acquisition period even when aphids were serially transferred onto fresh healthy plants on a daily basis. Transmission experiments determined that RpLV has a 6-day latent period in the aphid before it becomes transmissible; however, it was not transmitted transovarially to the next generation. To our knowledge this is the first report of a plant reovirus transmitted by an aphid.