Rock-Crawlers: Grylloblattodea

Rock-crawlers are typically found singly or in sexual pairs and are active at night.

Some North American species look for food on the surface of the snow. They detect prey and other food items with their mouthparts. The larvae can survive without food for three to six months. Although they are adapted for survival at cooler temperatures, rock-crawlers will die if they are caught in extended periods of freezing temperatures. They will also die if temperatures rise to 82°F (28°C).

Courtship takes place under stones and includes lots of leg nibbling and touching with the antennae. Occasionally, the female may suddenly eat the male. Females lay sixty to 150 eggs in or on the soil, in decayed wood, or under leaves and stones. The eggs hatch in about 150 days but may take as long as three years. The larvae strongly resemble the adults when they hatch and gradually get larger as they mature. They molt, or shed their outer covering, or exoskeleton, three times during the first year and once a year for the next four or more years before reaching adulthood.