People have been finding “large mosquitoes” in their homes this month. Fortunately, they aren’t actually mosquitoes but a related insect know as a crane fly. Crane flies are common insects in Minnesota. You can recognize them from their slender brown or gray bodies and long, slender legs. Most crane flies range in size from 3/8 to 1 ½ inches long. Entomologists look for a ‘V’ shaped suture on the thorax to help identify crane flies.
Crane flies are common throughout the spring and summer. Outdoors, they are usually
|Crane fly found indoors in author's home. |
Photo: Jeff Hahn, UMN Extension
However, they do startle people when they appear indoors in the middle of winter. Where do they come from? In most cases, it is likely that the source of crane flies found indoors can be traced back to houseplants that were outside at some point during the summer. Female crane flies laid eggs in the soil and the larvae finished their development indoors and emerged as adults. There is not any special action that needs to be taken when these harmless insects are found indoors; physical removal is the only necessary control.