Lesser dung fly (genus Coproica)

The genus Coproica belongs to the family Sphaeroceridae within the order Diptera. These small flies, commonly referred to as lesser dung flies, are ecologically significant as decomposers, but under specific environmental conditions, they can become problematic pests in commercial horticulture and greenhouse systems.

These pests are particularly attracted to environments with high organic matter content and excessive moisture. They are frequently found in greenhouses where decomposing compost, manure, or plant debris provides a continuous source of nutrients for their larvae, often leading to rapid population explosions if left unchecked.

The life cycle consists of egg, larval, pupal, and adult stages. Females lay eggs in moist organic substrates. Once hatched, larvae feed voraciously on decaying material but can transition to feeding on weakened plant roots or stems, especially in seedlings that are already suffering from poor soil aeration or excess dampness.

The damage caused by Coproica is characterized by root scarring and tissue mining at the base of the plant. These feeding sites act as entry points for phytopathogenic fungi and bacteria, which often cause severe root rot. Infected plants exhibit stunted growth, chlorosis, and, in severe cases, may collapse or die prematurely.

Effective management strategies for these flies focus on cultural control and sanitation. It is essential to remove rotting plant debris and maintain optimal irrigation practices to avoid waterlogging the soil. Yellow sticky traps are highly effective for monitoring and reducing adult fly populations, while soil drenches with entomopathogenic fungi offer a reliable biological control method.