Thread subject: :: Entomophthora muscae

Posted by Jim Senn on 14-01-2022 16:39

My observations & conclusions -- maybe this will interest somebody. I found 4 dead flies; 2 on 9 Aug., 1 on 10 Aug., & 1 on 12 Aug. 2021 hanging on the underside of a Zwetgen (a prune type plum) leaf by their tongues. The plum tree had aphids that were secreting "dew" & attracting wasps, bees, & flies. I took photos of the last 2 & found they had Entomophthora muscae fungus. Upon reading about this fungus I would question two current "facts". It makes sense to me that the primary infectious route is oral; especially since, these flies have large tongues & the spores erupt from the fungus to contaminate a large area under & around the dead flies: NOT by spores landing on healthy flies & penetrating their "skin" to infect them. Secondly, it is reported that the flies suck themselves to a surface just before they die and die in convulsions where they remain hanging after death. The flies I observed remained hanging by their tongues for several days which would be an astonishing feat for muscles that are dead & thus should no longer have sucking ability. What appears to have happened is that the flies tried to feed on something & the fungus, that was growing on their tongues, attached them to the surface. Once attached, they struggle (convulse) trying to release their tongue & eventually die. See photo of attached tongue. (Prob with attaching photo.)