The fungus that most commonly infects flies, particularly house flies ( Musca domestica) and cluster flies (Pollenia rudis), is Entomophthora muscae.
Entomophthora muscae: The Fly Killer
Entomophthora muscae is a pathogenic fungus that specifically targets and kills various fly species. The name itself, "Entomophthora," means "insect destroyer," aptly describing its deadly effect.
How the Infection Works
The infection process is quite fascinating:
- Spore Attachment: The fungus releases spores that land on a fly.
- Penetration: The spore germinates and penetrates the fly's exoskeleton.
- Internal Growth: Inside the fly, the fungus grows, consuming the fly's tissues.
- Behavioral Manipulation: As the infection progresses, the fungus manipulates the fly's behavior, often causing it to climb to a high point.
- Death and Spore Release: The fly dies, typically attached to a surface with its legs extended. The fungus then erupts from the fly's body, releasing new spores to infect other flies. This eruption often leaves a characteristic halo of spores around the dead fly.
Signs of Infection
You can often identify flies infected with Entomophthora muscae by the following:
- Elevated Position: The fly is often found dead in an elevated position, clinging to a window, plant, or other high surface.
- Extended Wings: The fly's wings are often outstretched.
- Halo of Spores: A visible halo of spores may be present around the dead fly.
- Swollen Abdomen: The fly's abdomen may appear swollen due to the fungal growth inside.
Other Fly-Infecting Fungi
While Entomophthora muscae is the most common, other fungi can also infect flies, although typically less frequently. These include species from the genera Beauveria, Metarhizium, and Aspergillus. These fungi are often less host-specific than E. muscae and can infect a wider range of insects.
Importance of Understanding Fly-Infecting Fungi
Understanding these fungi is important for several reasons:
- Natural Pest Control: These fungi can act as natural biocontrol agents, helping to regulate fly populations.
- Disease Ecology: Studying these interactions provides insights into the ecology of infectious diseases.
- Potential Biopesticides: Research into these fungi could lead to the development of novel biopesticides.
