A novel potyvirus is first described from Passiflora foetida from the Indonesian province of Papua, the Torres Strait Islands and Cape York Peninsula, Queensland. Infected plants had yellow/green mosaic symptoms, sometimes ringspots and chlorotic spots, and were not infected by other known viruses. The virus was transmitted by Aphis gossypii in a non-persistent manner. Analysis of the core and 3′ regions of the coat protein sequence and the 3′ untranslated region revealed a potyvirus distinct from, but most closely related to, Zucchini yellow mosaic virus and Ceratobium mosaic virus. A reverse transcription PCR with colourimetric microplate detection was developed and the virus was subsequently shown to be widespread in commercial P. edulis hybrids in New South Wales and Queensland. The virus is tentatively named Passiflora virus Y.