Coffee ringspot virus (CoRSV), transmitted by the tenuipalpid mite Brevipalpus phoenicis, has been reported in many parts of Brazil and recently, in Costa Rica. Particularly in the Southern region of the State of Minas Gerais, it has been found in high incidence inducing some losses. CoRSV has particle morphology and cytopathic effect similar to Orchid fleck virus (OFV), transmitted by B. californicus. Systemic infection of some hosts as Chenopodium quinoa and Tetragonia expansa obtained by growing them in higher temperatures, permitted a partial purification of CoRSV, using a modified Chang et al. protocol for OFV, which yield rodlike particles with one round end, 45 nm x 100-140 nm, with a 25 nm axial channel and cross striations with a pitch of 4 nm. Agarose gel electrophoresis of the RNA extracted from these preparations produced 2 bands of 6,000 and 6,400 nts. Injection of semi-purified preparations into rabbit produced an antiserum. Comparative assays with anti-CoRSV and anti-OFV (Kondo et al., 1995) sera, previously adsorbed, with indirect ELISA, demonstrated highly specific reactions for homologous viruses, but no detectable cross-reaction. In situ immunocytochemistry resulted in significant labeling on the nuclear viroplasm present in CoRSV- or OFV-infected leaf cells in homologous reaction and slight labeling in heterologous reactions using anti-CoRSV and anti-OFV sera.