This photo was taken in 2012 during a visit to Mammoth Cave in Kentucky. Just as we were leaving, I had the misfortune to look up and find dozens of these huge, long-legged crickets crawling along the ceiling!
Cave crickets (there are several species, but the one specifically living in Mammoth Cave is Hadenoecus subterraneus) roost inside cave entrances in the southeastern United Stages. They leave the cave about every two weeks to feed on the surface, and bring back nutrients with them — a lot of cave life depends on the crickets’ guano, eggs, and carcasses and the nutrients they introduce to the cave ecosystem.
Cave crickets can also be found in human homes — they like basements, utility rooms, crawl spaces and other cool, damp locations. Outdoors they can also be found under stones and in woodpiles and tall grass. They aren’t exactly social in the same way that ants are, but they do tend to congregate together, forming large groups like the one I saw on the cave ceiling. The adults eat wood, fungi, other insects, carpet, cardboard, and sometimes even each other.
Unlike other species of cricket, cave crickets neither chirp nor fly (as they lack wings). They do leap long distances when startled, but they are not venomous and are generally harmless to humans.