Peanut earwig

The peanut earwig (Latin: Marava arachidis) belongs to the order Dermaptera and the family Spongiphoridae. As a cosmopolitan pest, it is frequently encountered in tropical and subtropical regions. It is well-known for its ability to thrive in man-made environments, including grain stores, greenhouses, and warehouses, where it poses a significant threat to stored agricultural products.

The host range of Marava arachidis is quite diverse. It primarily feeds on peanuts, various legumes, grains, and occasionally the succulent parts of vegetable crops in greenhouses. By damaging seeds and fruits, the insect causes substantial economic losses, especially when infestations occur in post-harvest storage facilities.

The biology of the peanut earwig is characterized by a relatively rapid life cycle under favourable conditions. Females demonstrate maternal care by tending to their eggs, which ensures a higher rate of survival for the nymphs. In temperature-controlled environments, the insect can reproduce continuously, leading to overlapping generations and persistent infestation pressure.

The damage caused by these insects is both direct and indirect. By chewing holes into seeds and fruit tissues, they allow pathogens to enter, which often leads to secondary infections like mold or rot. The presence of insect frass and webbing further contaminates the product, rendering it unsuitable for market or consumption.

Effective management and control strategies for the peanut earwig include:

• Improving sanitation in storage facilities to eliminate hiding spots.
• Controlling moisture levels to create an environment hostile to the pest's development.
• Monitoring pest populations using physical traps to prevent widespread outbreaks.
• Applying registered chemical or biological insecticides in severe infestation cases.