Thosea porthetes

Systematic position. Thosea porthetes is a species of moth belonging to the order Lepidoptera and the family Limacodidae, commonly known as cup moths or slug moths. The larvae are notorious for their slug-like appearance, which is a distinctive morphological trait used to identify this group of defoliators.

Host plants. This pest affects a wide range of economically important crops, including coffee, cacao, and various fruit-bearing trees. It thrives in plantation environments where consistent foliage provides both food and protection for developing larvae, leading to substantial infestation risks in tropical agricultural systems.

Biology and lifecycle. The lifecycle of Thosea porthetes follows a complete metamorphosis: egg, larva, pupa, and adult. The larval stage is the most critical for agricultural management. The pupal stage is spent within a resilient, hardened silk cocoon attached to the bark of the host plant, which allows the species to survive various environmental stresses during the dormant phase.

Nature of damage. Larval feeding behavior is the primary cause of damage. Young larvae typically skeletonize leaves, while older stages consume entire leaf blades. Heavy infestations result in severe defoliation, which causes significant physiological stress to the trees, resulting in reduced photosynthetic efficiency and substantial yield losses in commercial plantations.

Protection measures. Managing this pest requires an integrated approach to maintain crop health.

• Implementation of biological control agents such as parasitic wasps.
• Manual removal and destruction of visible cocoons during pruning cycles.
• Applying targeted microbial pesticides based on Bacillus thuringiensis.
• Regular field monitoring using light traps to determine adult flight periods and population peaks.