Common name(s): Rock crawlers, ice crawlers.
Description: Medium in size, soft-bodies, elongate, pale and wingless. Often eyeless, ocelli are absent. Prognathous mouthparts. Stout coxae on legs adapted for running. The cerci are 5-9 segmented. Females have short ovipositers, and male genitalia is asymmetrical. Nymphs resemble small pale adults.
Fun facts: There is just one family of grylloblattids containing 20 species, restricted to western North America and central to east Asia. These insects are particularly tolerant of cold and high elevations. Eggs may diapause for up to a year in moss or damp soil. Rock crawlers are active by day and night at low temperatures, feeding on dead arthropods and organic material, notable from the surface of ice and snow in the spring snow melt. However, they are also found in alpine soil and similar damp places.
The relationship of grylloblattids within the Insecta class is a bit uncertain, as there are so few of them. Limited molecular evidence suggests a relationship with Plecoptera and Dermaptera, but morphologically and embryologically, grylloblattids are closest to the orthopteroid insects.
sourced, in part, by The Insects: An outline of entomology, second ed. Gullan, P.J. and P.S. Cranston. Blackwell Science, Great Britain, 2000.