Boreus pilosus Carpenter 1935
Diagnosis: Body brown with yellowish-brown legs and wings, covered in long, white pilosity. Ratio of maxilla-labial complex to rostrum = .80. Anterior and posterior margins of pronotum with 2 to 6 yellowish-brown bristles. Meso- and metanota occasionally with 2 medial bristles each. Apicomedial femoral spine present. Male forewing with 19 – 22 medial spines and 16 – 19 lateral spines. Hindwing with 9 – 15 spines. Female forewing oval, covering hindwing. Male 8th tergum and sternum not fused; 9th tergum and sternum also not fused. Hood of male 9th tergum small, only about ¼ width of tergum, with medial, longitudinal cleft and no medial ridge. Only about 19 denticles on either side of cleft. Male 9th sternum apicomedially notched.
Distribution – Geographical: Adults of this species have been taken in western Montana to western Alberta and British Columbia in mountains at 4,000 to 6,200 feet.
Distribution – Temporal: Adults have been collected between 4 October and 11 April.
Ecology: The habitat of this species has been described as an alpine meadow on a snow-covered, windblown, northeast facing slope (Penny, 1977).
Biology: Nothing is known of immature stages or life cycle.
Notes: This species is a member of the nivoriundus species group with unfused 8th and 9th terga and sterna, with bristles on thoracic nota, and with a small tergal hood which lacks a medial ridge. Within this species group, B. pilosus and B. nix share a characteristic long pilosity over much of the body. The two species can be separated by frequently paler coloration of B. pilosus, as well as fewer denticles on the male 9th tergum.
Carpenter, F.M. 1935. New Nearctic Mecoptera, with Notes on other Species. Psyche. 42:105-122.
Penny, N.D. 1977. A systematic study of the Family Boreidae (Mecoptera). University of Kansas Science Bulletin, 51(5)141-217.