On sunflower leaf where its model, a common Polistes species, frequently occurs. Pease Creek Recreation Area, Charles Mix County, South Dakota. These uncommon neuropterans are sometimes called mantisflies or mantidflies. Their role in the food chain mimics that of preying mantids, as they capture insects and fight with those modified front legs. Most mantisflies are small, seldom more than an inch long and are specific mimics of certain hymenoptera and their relatives, the lacewings. There is one spectacular species in Arizona which I have seen only once, which mimics the big dark-winged Polistes over there. Few people indeed would quickly reach for one of these little guys hanging on the underside of a leaf, because of the incredible resemblance to Polistes wasps. Eggs are laid near the ground or close to ground-dwelling spider burrows and, for some species, the nests of wasps and bees. The tiny larvae are quite mobile and actively go "hunting" for their host of choice. I believe they enter the spider's body through the openings to the book lungs. So, they are predators while developing and as adults. They also make delightful pets and are fun to watch. Small species, especially those built like lacewings, frequently come to lights at night in Arizona.
Contributed by David Williams