Boreus brumalis Fitch, 1847
Diagnosis: This species is dark brown without long, white pilosity. The rostrum is 1.68 to 2.07 times the vertical width of the compound eyes. Pronotum bears four bristles along both anterior and posterior margins. Male forewing abruptly narrowed at mid-length, with rows of 20 inner and 15 outer spines. Three spines on hindwing. Female forewing pad overlaps hindwing pad. Male abdominal hood approximately 1/3 width of ninth tergite and bearing a medial groove. Male ninth sternite medially notched at apex.
Distribution – Geographical: This species is widespread over the northeastern United States and southern Quebec south to the higher peaks of Tennessee and westward to the Wisconsin Dells and southern tip of Illinois.
Distribution – Temporal: Adults have been generally collected from 19 November until 24 April with one male and one female collected on 15 August.
Ecology: Larvae can be found on rhizoids of Dicranella heteromalla and Atrichum angustatum mosses in southern Illinois on sandy loam soils in forests (Stannard, 1957).
Biology: Larvae of different sizes can be found in tunnels beneath the moss rhizoids at all times of the year. It is not known whether the life cycle is one or two years.
Notes: This is one of two species of Boreus found in eastern North America (B. brumalis and B. nivoriundus). Males of both species have a notched ninth sternite. The two species can be separated by the smaller size and darker coloration of B. brumalis. This species is similar to B. bomari found in the western U.S., but can be separated by the more abrupt narrowing of male forewings at mid-length and the comparatively longer rostrum: 1.68 to 2.07 times vertical width of the compound eyes in B. brumalis and 1.29 to 1.33 times in B. bomari (Byers & Shaw, 2000).
The name brumalis comes from the Latin word bruma, meaning shortest day, or winter solstice, and refers to the winter activity of adults.
Byers, G.W. and S.R. Shaw. 1999 . A new species of Boreus (Mecoptera: Boreidae) from Wyoming. Journal of the Kansas Entomological Society 72(3):322-326.
Penny, N.D. 1977. A systematic study of the Family Boreidae (Mecoptera). University of Kansas Science Bulletin, 51(5)141-217.
Stannard, L.J. 1957. The first Records of Boreus (Boreidae, Mecoptera) in Illinois. Transactions of the Illinois State Academy of Science, 50:279-280.