Agraylea multipunctata

Systematic position: Agraylea multipunctata is a species of micro-caddisfly belonging to the order Trichoptera and the family Hydroptilidae. These insects are commonly found in freshwater habitats, where their larval stages inhabit submerged vegetation or stones, playing a role in the aquatic food web.

Biology and life cycle: The life cycle is complex, involving four stages: egg, larva, pupa, and adult. Females deposit eggs on aquatic substrates. Larvae are known for constructing portable cases from silk and leaf fragments. As they develop, they grow rapidly, feeding on algae and biofilms, eventually undergoing pupation before emerging as winged adults that are attracted to light.

Damage characteristics: While usually harmless in natural ecosystems, they can become pests in aquaculture, hydroponics, or water gardens. The larvae use their mouthparts to scrape algae from plant surfaces; however, in high population densities, they can damage the epidermis of young aquatic plants, causing aesthetic and physiological decline.

Economic impact: Their impact is most significant in nursery ponds or systems producing high-value aquatic plants. Excessive feeding and the physical presence of larvae can lead to stunted growth of plants, poor aesthetic quality, and secondary pathogen entry points on damaged leaf tissues, which lowers the commercial value of the crop.

Control measures: Managing Agraylea multipunctata requires an integrated pest management (IPM) strategy tailored for aquatic environments:

• Mechanical removal of excessive vegetation to reduce oviposition sites.
• Water level manipulation to expose and desiccate larvae and pupae.
• Introducing biological control agents, such as insectivorous fish species.
• Installing light traps to reduce the population of reproductive adults during the peak flight season.