Maple Callus Borer

When I first noticed this clear-winged insect working the collection of sedum flowers that carpet the area near our driveway, I had to admit that I couldn't immediately identify it. In fact, I wasn't even really sure what kind of creature it was. The remarkable feature, besides the window-pane wings, is that fan of red "feathers" at the back end of its abdomen. The reddish head was pretty memorable, too. A variety of field guide searches, both in my collection of actual books and online, pointed me towards taxonomic nirvana and a group of wasp mimics known collectively as "Clearwing Borers." These members of the lepidopteran family Sesiidae all have larvae that burrow into the woody parts of shrubs and trees, and some of them are agricultural and forest pests. The adults, however, are harmless enough, and the resemblance they bear to wasps is so uncanny that I'll leave them alone, savor their unexpected appearances, and, of course, document their presence. This one, I think, is a Maple Callus Borer, which, if I'm right—the wing markings aren't quite a field guide match, but there's always some variation on the main theme—is known in the trade as Synanthedon acerni.