cacao yellow mosaic virus cacao yellow mosaic virus cacao yellow mosaic virus (cymv) is a virus in the family tymoviridae that infects cacao trees in sierra leone. cacao yellow mosaic virus virus classification (unranked): virus realm: riboviria kingdom: orthornavirae phylum: kitrinoviricota class: alsuviricetes order: tymovirales family: tymoviridae genus: tymovirus species: cacao yellow mosaic virus description cymv, like other tymoviridae are non-enveloped viruses, surrounded by a capsid approximately 30 nanometers wide. the viral capsid has t = 3 symmetry. tymoviridae have positive-sense single-stranded rna genomes approximately 6 kilobases long. disease in the cacao tree, cymv infection leads to the appearance of large circular yellow blotches on the leaves. infected trees are not killed or severely inhibited. ecology and distribution cymv has only been found in sierra leone where it primarily infects the cacao tree theobroma cacao. however, it can experimentally infect a number of other dicots including chenopodium amaranticolor, chenopodium quinoa, tetragonia expansa, vinca rosea, nicotiana clevelandii, and nicandra physalodes.