Subject: what insect is this?
Location: Baltimore County, MD
June 30, 2013 3:58 pm
We live near a pond in Maryland. We have been here for 4 years and have not seen this insect until now. They came out of nowhere and swarmed around the lights and the windows anywhere there was light. What is it? Thanks.
This is a female Stonefly in the order Plecoptera, and she is carrying about her egg mass. Soneflies have aquatic larvae known as naiads, so the nearby pond is likely a factor in the sudden appearance. Here is a similar photo from BugGuide. The BugGuide page for the order indicates: “females deposit several egg masses, which together may total more than 1,000 eggs, by flying over water or occasionally by crawling up to the water; some nymphs are known to molt 12-36 times, and require one to three years to mature; full-grown nymphs leave the water, cling to shoreline vegetation and debris, and molt into the adult stage” and “nymphs of most spp. develop in cool, well-oxygenated water and do not tolerate pollution; therefore, their presence is an indicator of good water quality, and their absence in areas where they previously occurred may indicate pollution.”