Macrodactylus nigripes

Systematic position: Macrodactylus nigripes belongs to the order Coleoptera and the family Scarabaeidae. This species is recognized as a significant agricultural pest in its native range, where its larvae and adults can cause substantial economic losses in various cropping systems.

Affected crops: As a polyphagous insect, this beetle has a wide host range. It frequently attacks staple crops such as corn, soybeans, and beans, alongside various fruit and ornamental tree species. The feeding habits of the adult stage are particularly destructive to reproductive plant structures.

Biology and lifecycle: The lifecycle follows complete metamorphosis, comprising egg, larval, pupal, and adult stages. Larvae typically reside in the soil profile, where they feed on organic matter and plant roots, often causing underground damage that goes unnoticed until plants show signs of wilt. Adults emerge to feed and mate, often in synchronized bursts.

Type of damage: The most visible damage is caused by adults, which feed aggressively on the above-ground parts of the plant.

• Skeletonization of leaves, leaving only veins.
• Severe damage to floral buds and developing reproductive tissues.
• Reduction in photosynthetic capacity and overall crop vigor.

Control measures: Management requires an integrated approach. Cultural practices, such as deep tillage to disrupt larval development and crop rotation, are fundamental. When threshold levels are exceeded, the application of targeted insecticides during the peak activity of adults is necessary. Biological control using entomopathogenic fungi also represents a promising avenue for sustainable population management.