Australian citrus whitefly

Damage
Whiteflies have a piercing-sucking mouthpart that they insert into the plant tissue to feed on leaves. Leaves may wilt and drop as a result of feeding damage if populations are high.
Large quantities of a sweet sugary material known as honeydew are also secreted by the whiteflies. Leaves and fruit often turn black with the growth of sooty mould fungus on the honey dew.
Lemon trees are the favourite host, but all types of citrus are vulnerable to attack.