Tricholyga sorbillans

Tricholyga sorbillans (often classified within the Exorista genus) is a species of parasitic fly belonging to the Tachinidae family within the order Diptera. While these insects act as natural predators for various agricultural pests in the wild, they are recognized as significant threats in the sericulture industry due to their parasitism on silkworm larvae.

The host range of this fly includes numerous lepidopteran species, including various moth larvae that are considered pests in forestry and field crops. By attacking these insects, the fly functions as a natural regulator of populations, helping to keep certain pest densities in check within forest ecosystems and open agricultural landscapes.

The life cycle is highly specialized. The female fly deposits eggs directly onto the surface of the host's body. Upon hatching, the larvae penetrate the host's integument and begin feeding on its internal tissues. This feeding process typically continues until the host dies, after which the parasite leaves the remains to pupate in the soil or protected crevices.

In sericulture, the presence of Tricholyga sorbillans poses a major challenge. When these flies infiltrate silkworm rearing facilities, they can cause widespread mortality among silkworm larvae. The resulting damage can be catastrophic for cocoon production, leading to severe economic losses for silk farmers who rely on healthy larval development.

Mitigation strategies primarily focus on preventing access to rearing environments:

• Installation of fine-mesh screening on all windows, doors, and air vents of rearing facilities.
• Implementing rigorous hygiene standards to minimize the presence of attractants for adult flies.
• Regular inspection of larvae to detect and remove individuals carrying fly eggs.
• Strategic placement of traps if fly populations are observed near production sites.