Grey silverfish

Systematic position. The grey silverfish (Ctenolepisma longicaudata) is a member of the order Zygentoma and the family Lepismatidae. It is a wingless insect characterized by a silver-grey color and a slender, tapering body with three prominent filaments at the posterior end, making it highly distinct from other common indoor insects.

Crops damaged. Although typically associated with households, these insects can become serious pests in greenhouses, storage facilities, and nurseries. They feed on various organic materials, including seeds, germinating seedlings, starch-rich plant tissues, and herbarium collections, which can lead to significant economic losses in sensitive areas.

Biology and life cycle. These insects prefer warm and humid environments, which are conducive to their survival and reproduction. The life cycle involves a nymphal stage that progresses through multiple molts; remarkably, unlike most insects, Ctenolepisma longicaudata continues to molt throughout its adult life, which can span several years under favorable conditions.

Damage and pest status. Damage is typically manifested as irregular feeding marks on leaves, bored holes in seeds, and damage to plant tissue surfaces. Their presence is often detected by the observation of the insects themselves or the damage to stored seed inventory, which often results in decreased germination rates and reduced aesthetic value of ornamental plants.

Control measures. Effective management focuses on habitat modification and sanitation to prevent infestation:

• Reducing indoor humidity levels to below 50% to inhibit reproduction.
• Regular cleaning to remove organic debris that serves as a food source.
• Sealing cracks and crevices where insects hide and breed.
• Application of targeted insecticide baits or silica-based dusts in infested areas.