Apium virus Y (AVY) is a plant pathogenic virus in the genus Potyvirus and the virus family Potyviridae. Apium virus Y is a recently described member of the potyvirus family. It was first found in Australia in 2002 in poison hemlock (Conium maculatum: an immigrant weed in Australia). A survey of native and weed species in the family Apiaceae found ApVY to be widespread in Australia. In addition, this survey and others found two other potyviruses. One was a well-known potyvirus infecting the Apiaceae, Celery mosaic virus (CeMV). CeMV has been found in celery (Apium graveolens) crops worldwide, including Australia, New Zealand and the US. The third potyvirus found in these surveys was another previously unknown potyvirus, Carrot virus Y (CarVY).