Rock-Crawlers: Grylloblattodea

Rock-crawlers are slender, flattened, soft-bodied insects. Adults range from 0.6 to 1.4 inches (15 to 35 millimeters) in length. They are mostly brown, while the legs and underside are light brown. The larvae (LAR-vee), or young, form of the animal, which must go through changes in form before becoming an adult, are white, yellowish, or sometimes black. The head is short, with small compound eyes present or absent, depending on species. Their chewing mouthparts point forward. The antennae (an-TEH-nee), or sense organs, are threadlike and made up of twenty-eight to fifty segments. Rock-crawlers never have wings, and all of their legs are long and thin. The abdomen has ten segments, with a pair of long, segmented structures at the tip.