Ireland

Damson hop aphid (Hop Aphid)

Phorodon humuli

Identification: Phorodon humuli apterae are small to medium sized, whitish to pale yellowish green and relatively shiny. The abdomen is marked with three dark green longitudinal stripes. The head has the characteristic pair of elongate projections on the inside of the antennal tubercles. The siphunculi are pale with slightly dusky tips and over twice as long as the pale cauda. The body length of Phorodon humuli is 2.0-2.6 mm on plum, and 1.1-1.8 mm on hop.

The damson-hop aphid host alternates from blackthorn or plum (Prunaceae) to hops (Cannabinaceae). It does not cause leaf curling itself but often lives on plum leaves distorted by Brachycaudus helichrysi. Migration of winged forms to hops takes place from late spring. There is a return migration to the winter hosts in September where sexual forms are produced and eggs laid. Phorodon humuli is indigenous to Europe and neighbouring areas, but has been introduced to North America and New Zealand.