Coffee pit scale

Taxonomic position. The coffee pit scale (Asterolecanium coffeae) is a member of the order Hemiptera and the family Asterolecaniidae. This insect is a specialized sap-sucking pest known for its ability to form protective tests (scales) that make it resistant to many external environmental factors.

Host plants. The primary host for this pest is the coffee plant (Coffea spp.). However, it can also infest various other woody ornamental plants grown in tropical and subtropical greenhouse conditions, acting as a significant phytosanitary threat in many agricultural regions.

Biology and life cycle. The life cycle involves the development of sedentary females protected by waxy, pit-forming tests on the plant surface. The most mobile stage is the crawler (first-instar larva), which moves to suitable feeding sites on the stems or leaves to settle and begin its development into an adult.

Nature of damage. The pest damages host plants by inserting its stylets into the plant tissues and extracting sap. This feeding process leads to the formation of characteristic pits or depressions. Heavy infestations result in stunted growth, leaf chlorosis, twig dieback, and the presence of honeydew which often promotes the growth of sooty mold.

Control measures. Integrated Pest Management (IPM) is essential for controlling this scale insect. Strategies include:

• Regular monitoring for crawler activity to time insecticide applications.
• Using systemic insecticides that are absorbed by the plant and target feeding insects.
• Pruning and destroying heavily infested branches to reduce the overall population.
• Encouraging natural enemies, such as parasitoid wasps, where applicable.