Boreidae
Guides
Boreus coloradensis
snow scorpionfly
Boreus coloradensis is a species of snow scorpionfly in the family Boreidae, described by Byers in 1955. Despite their common name, these insects are neither scorpions nor true flies. Adults are active during winter months and have been observed on snow, ice, and moss. They belong to one of the smallest insect orders, Mecoptera, and are believed to be ancient relatives of fleas.
Boreus elegans
snow scorpionfly
Boreus elegans is a species of snow scorpionfly in the family Boreidae, described by Carpenter in 1935. Like other members of its genus, it is adapted to cold environments and is active during winter months when most other insects are dormant. The species is found in North America. Snow scorpionflies are characterized by their reduced wings and distinctive jumping ability.
Boreus reductus
Snow scorpionfly
Boreus reductus is a wingless species of snow scorpionfly in the family Boreidae, order Mecoptera. Adults are active during winter months and can be observed hopping across snow and ice. Unlike many Mecoptera, this species lacks functional wings entirely. Adults and larvae feed on mosses and liverworts. Males possess enlarged, upward-curving genitalia that resemble a scorpion's stinger, giving the group its common name. The species engages in a distinctive mating behavior where males carry females on their backs.
Caurinus
snow scorpionflies
Caurinus is a genus of snow scorpionflies in the family Boreidae, containing two described species: Caurinus dectes from Washington and Oregon, and Caurinus tlagu from Alaska. These tiny, flea-like insects are among the most unusual members of Mecoptera, with a fossil lineage dating back over 145 million years to the Jurassic. They are non-parasitic and feed on leafy liverworts in coastal forest habitats.
Hesperoboreus
Hesperoboreus is a genus of snow scorpionflies (Mecoptera: Boreidae) established by Norman Penny in 1977. Members of this genus are small, wingless insects adapted to cold environments. The genus is distinguished from the related Boreus by morphological features of the male genitalia. Very few observations exist, with only three records documented on iNaturalist as of the knowledge cutoff.
Mecoptera
Scorpionflies, Hangingflies, Snow scorpionflies
Mecoptera is a small order of holometabolous insects comprising approximately 600 extant species in nine families worldwide. The group includes scorpionflies (Panorpidae), hangingflies (Bittacidae), and snow scorpionflies (Boreidae). Males of the largest family, Panorpidae, possess enlarged genital structures that resemble scorpion stingers, giving the group its common name. The order exhibits close phylogenetic relationships with Siphonaptera (fleas) and Diptera (true flies), with some studies suggesting fleas may be derived from within Mecoptera, rendering the order potentially paraphyletic. Modern mecopterans are primarily found in moist environments, though the Boreidae are adapted to cold montane regions where adults walk on snowfields.