Aleurocanthus woglumi (citrus blackfly)

Sticky honeydew deposits accumulate on leaves and stems and usually develop black sooty mould fungus, giving the foliage (even the whole plant) a sooty appearance. Ants may be attracted by the honeydew. Infested leaves may be distorted. The insects are most noticeable as groups of very small, black spiny lumps on leaf undersides.

Feeding by A. woglumi damages new leaf growth, reducing nitrogen levels in infested leaves. Sooty mould growing on honeydew deposits blocks light and air from the leaves, reducing photosynthesis. This can reduce fruit set by up to 80% or more (Eberling, 1954). Crop losses of limes due to A. woglumi were recorded at 25% by Watts and Alam (1973). In Mexico, citrus blackfly is regarded as a threat to citrus crops and to other crops such as mangoes, pears or coffee grown adjacent to heavily infested citrus groves. A. woglumi is a constant menace to citrus and other crops in the USA and Venezuela. It has been recorded seriously affecting citrus in India (David and Subramaniam, 1976). Le Pelley (1968) mentions it as a severe pest of coffee in the New World.