Antestia bugs (Antestiopsis spp)
Antestia bugs are major pest of Arabica coffee in East African countries. The adult bug is shield-shaped, about 6 to 8 mm long and strikingly coloured dark brown with orange and white markings. They hide in berry or flower clusters. Females lay eggs in groups of about 12 on the underside of leaves. Newly hatched nymphs are about 1 mm long. Nymphs resemble the adults in colour but have a more rounded shape and lack functional wings.
Both adults and nymphs cause severe damage to green berries by feeding and indirectly by the transmission of a fungus (Nematospora coryli), which causes rotting of beans. The bug also attacks flower buds and shoots causing blackening of flower buds with no flower/fruit set. Attacked branches grow side shoots (fan branching). No visible surface marks / scars or wounds on berry are noticeable until seen on drying beds as "zebra" beans. "Zebra" beans produce poor quality coffee and are possible avenues for fungal infection. Antestia bugs can live on shrubs belonging to the same family as coffee (Rubiaceae family).
- Naturally occurring parasitic wasps attack antestia eggs. Attacked eggs are black while normal eggs are white.
- Undertake regular and timely pruning and desuckering. Antestia bugs prefer dense foliage.
- Spraying with Neem has been recommended when more than 3 bugs per tree are found in Tanzania, and 2 bugs are found per tree in drier areas and more than 1 bug per tree in wetter areas in Kenya.