Boreidae, commonly called snow scorpionflies, or in the British Isles, snow fleas are a very small family of scorpionflies, containing only around 30 species, all of which are boreal or high-altitude species in the Northern Hemisphere.
Phylogeny
It is unclear as of 2020 whether the Mecoptera form a single clade, or whether the Siphonaptera (fleas) are inside that clade, so that the traditional "Mecoptera" is paraphyletic. However the earlier suggestion that the Siphonaptera are sister to the Boreidae is not supported. The two possible trees are shown below: (a) Mecoptera is paraphyletic, Boreidae is sister to (Nannochoristidae + Siphonaptera): }} (b) Mecoptera is monophyletic, Boreidae is sister to Pistillifera: }} ==Genera==
Genera
This list is adapted from the World Checklist of extant Mecoptera species, and is complete as of 1997. The number of species in each genus is indicated in parentheses. • Boreus (24) Latreille, 1816 (North America, Europe, Asia) • Boreus hyemalis – also called the snow flea. • Caurinus (2) Russell, 1979 (Oregon, Alaska) • Hesperoboreus (2) Penny, 1977 (United States) == See also ==