Image Credit: Gilles Gonthier
Leaf-mining flies (Anthomyiidae, Muscidae) – herbivores (living & decaying leaves). In alpine communities, there are often enormous populations and species richness of anthomyiid flies that inhabit stream banks and snowmelt puddles (i.e., several dozen species in a single marshy snowmelt wetland). Most bees (even bumblebees) tend to avoid the sites with standing water, but there can be dense flowering of buttercups (Ranunculus), cinquefoil (Potentilla), Veronica and St John’s wort (Hypericum). These flies are attracted to dish-shaped flowers, and when bees and syrphid flies are absent, they are the most significant pollinators.
Leaf-mining flies (top row) and true house-flies (bottom row) are very similar. They are distinguished by a character of the wing veination only. The actual house-fly (bottom right) is only an occasional flower visitor in backyard settings.