Rock-Crawlers: Grylloblattodea

All twenty-seven species of rock-crawlers live in the Northern Hemisphere; they are found in Siberia, northeastern China, Korea, and Japan. Eleven species are known to live in the United States and Canada.

Rock-crawlers are secretive animals that live at elevations between 656 and 10,499 feet (between 200 and 3,200 meters) in mixed forests or in mountains above the highest point where trees can grow, usually near snowfields. They prefer cooler temperatures, of about 38.7°F to 60°F (3.7°C to 15.5°C), and are found in moist habitats beneath rocks and in crevices (KREH-vuh-ses) in rocky snowfields or inside subterranean lava tubes.

Both adults and young eat the soft tissues of captured and dead insects and spiders. The larvae also eat parts of plants and other bits of plant or animal tissues in the soil.

Rock-crawlers are important research animals for scientists studying how animals survive in cold temperatures. The distribution of rock-crawlers may also provide clues about where ancient animals lived during the Ice Ages over the past two million years.

Only one species of rock-crawler is listed by the World Conservation Union (IUCN). The Mount Saint Helens rock-crawler is listed as Vulnerable, or facing a high risk of extinction in the wild. It is found in the U.S. Pacific Northwest.