Rough weevil

Taxonomic classification. This species belongs to the order Coleoptera and the family Curculionidae. It is a small, cryptic weevil species that is often overlooked in field inspections due to its coloration, which blends perfectly with soil particles and leaf litter, and its nocturnal behavioral patterns.

Host plants and damage. The species is known to infest a variety of plants, including strawberry crops and various ornamental perennial species. Adults primarily damage foliage, while the larvae feed on the root systems. This dual-stage damage makes the pest particularly detrimental to young transplants and nursery stock, which have less established root resilience.

Biology and lifecycle. The lifecycle consists of a complete metamorphosis. Adults typically overwinter in the upper soil layers or beneath debris. Once temperatures rise in the spring, they emerge to feed and mate. Females deposit eggs directly into the soil near the root zone of host plants, where larvae emerge and immediately begin feeding on root tissues.

Nature of damage. Adults feed at night, leaving irregular, scalloped notches along the leaf margins. During the day, they remain hidden in the soil. The larval stage is often more destructive, as feeding on the root system weakens the plant, restricts nutrient uptake, and makes the plant susceptible to secondary pathogens and wilting.

Control measures. Integrated Pest Management (IPM) is essential for controlling this weevil.

• Crop rotation to break the cycle of soil-borne larvae.
• Soil cultivation during the larval development stage to expose them to predators.
• Targeted application of insecticides during the nocturnal activity window.
• Use of biological controls, such as entomopathogenic nematodes applied to the soil to target larvae directly.