Explanation of Names
BOREUS: probably from "boreal" (northern) - referring to the mostly northern distribution of the genus
Numbers
10 species in North America (
nearctica.com)
15 additional species in Eurasia (California Academy of Sciences)
species diversity greatest in western North America (8 species); only 2 species occur in the east: brumalis and nivoriundus
Identification
Adult: usually dark-colored with an elongated rostrum ("beak"), long antennae, vestigial wings, and long hind legs adapted to jumping; female has a straight ovipositor about the same length as the rostrum, and tapering to a point; males have a blunt rounded abdominal tip
Range
Alaska to New Brunswick, south in the east to Virginia and Tennessee, south in the west to California and Arizona
Habitat
on surface of snow at high elevations in southern part of range; on snow in various habitats farther north
Season
adults active from November to March in southern part of range; spring and summer in the far north (e.g. Alaska)
Food
larvae and adults feed on leafy parts of mosses
Remarks
The mating behavior of Boreus species differs from other Mecoptera. The male grasps the female with his slender, hardened wings and moves her to a position above his back, with the lower part of her elongate ovipositor inserted into his ninth (genital) segment. [George Byers, Emporia U., Kansas]
See
photo of mating couple. The female, at left, on the male's back, has the base of her ovipositor contacting the tip of the male's upturned abdomen. This female-on-top position is unusual in the insect world.
Internet References
description, habitat, mating behavior and live image of adults mating (George Byers, Emporia U., Kansas)
Winter Insects of Eastern New York; PDF doc - photocopy of the original detailed technical description of
Boreus nivoriundus and
B. brumalis by Asa Fitch in 1847 (Walter Reed Biosystematics Unit, Smithsonian Institution)
checklist and distribution of worldwide species, listing states, provinces, or countries of each species (California Academy of Sciences)
pinned adult images labeled as male and female "probably
brumalis" but in fact are two females of
B. nivoriundus (Insects of Quebec)