Jeffrey Hahn, Asst. Extension Entomologist
Several people reported recently finding a small, ½ inch long, insect that resembles a preying mantid and a paper wasp. This unusual looking insect is known as a mantidfly. It looks like a preying mantid because of its large, front legs which are modified for grabbing prey. Mantidflies are commonly reddish brown with yellow with wings that are half brown along the front margin half and clear. Although they may not be frequently seen, mantidflies are reasonably common in Minnesota.
Mantidflies commonly parasitize spiders while other species lay eggs in the soil where the larvae prey on scarab beetle grubs, noctuid moth larvae, or social wasps. Adults feed on small insects they capture. Mantidflies are common on foliage in wooded areas during summer. People have generally found these insects outdoors but in at least one case a mantidfly was found that had accidently entered a house. Fortunately, these insects are harmless to people. If you should find one in your home, just release it outdoors.