Rock-Crawlers: Grylloblattodea

Physical characteristics: The adults measure 0.98 to 1.06 inches (25 to 27 millimeters) in length. Their bodies are yellowish brown. The antennae have fewer than thirty segments.

Geographic range: Northern rock-crawlers are found in southeastern British Columbia, southwestern Alberta, eastern Washington, northern Idaho, western and southern Montana.

Habitat: Northern rock-crawlers live in the mountains above the highest point where trees can grow. They prefer habitats where there is plenty of moisture and the temperatures range between 38°F and 60°F (3°C and 15°C), such as the edges of glacial bogs in moss, decaying wood, or damp areas deep under rocks. They are sometimes buried up to 3.3 feet (1 meter) in piles of pebbles, small stones, and other rocky debris.

Northern rock-crawlers live alone or in pairs. They avoid light and forage for food at night on and around snowfields. (Illustration by Marguette Dongvillo. Reproduced by permission.)

Diet: Adults find and eat mostly small, dead insects, especially wingless crane flies. The larvae scavenge dead insects but also feed on some plant tissues.

Behavior and reproduction: Northern rock-crawlers live alone or in pairs. They avoid light and forage for food at night on and around snowfields. Although they prefer to live at cooler temperatures, they will die if exposed to long periods of freezing temperatures. The larvae may take up to seven years to reach adulthood.

Northern rock-crawlers and people: This insect is an important research animal for scientists studying how organisms survive at low temperatures. They are used as the official symbol of a scientific organization that studies insects, the Entomological Society of Canada, as well as of the Department of Entomology at Montana State University in Bozeman.

Conservation status: This species is not endangered or threatened. ∎