Crop & Pest Report


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Mystery Insect (06/18/20)

What is this fly doing in the pictures? Is it a pest?

What is this fly doing in the pictures? Is it a pest?


Answer:  These flies are infected with a pathogen. Those light stripes on the dead flies are spores of the Entomophthora fungus. The fungus seems to interfere with the flies' coordination. They land on a plant and crawl out to the edge of a leaf or twig and die. This ensures that the fungal spores can disperse freely and infect more flies or insects. Under humid, warm and moist condition, epizootics can occur and provide excellent natural control of insects.


Janet J. Knodel

Extension Entomologist


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