Snow Scorpionflies (Mecoptera: Boreidae) of the Hanford Reach National Monument

Abstract

Boreidae are a small and intriguing family of insects in the order Mecoptera. Also called snow scorpionfiies, adults are active in the winter months and thus rarely collected. They are associated with mosses and other bryophytes on which they feed, plants that are prominent components of the biological soil crusts common in shrub-steppe environments. Large series of Boreus californicus, B.nix, and B. reductus were collected in pitfall traps and by hand during surveys conducted from 1998-2002, at what is now the Hanford Reach National Monument. Eleven collecting sites were pitfall trapped in winter during the study, with specimens collected at only three of the locations. All but one of the pitfall-trapped specimens came from two adjacent collecting sites. Specimens were also hand-collected from Rattlesnake Ridge, within 5km of the productive pitfall trap sites. Adults were collected from November through April but were most abundant in December and January. Sex ratios for all species and both collecting methods were generally male dominated. The continuous sampling during this project provides a rare look at the phenology and community composition of shrub-steppe Boreus but does little to elucidate Boreus spp. habitat selection.