''Boreus hyemalis'' (Syn.: ''Boreus hiemalis'') is an

insect Insects (from Latin ') are pancrustacean hexapod invertebrates of the class Insecta. They are the largest group within the arthropod phylum. Insects have a chitinous exoskeleton, a three-part body ( head, thorax and abdomen), three ...

, 3 to 4.5 millimetres long from the

family Family (from la, familia) is a group of people related either by consanguinity (by recognized birth) or affinity (by marriage or other relationship). The purpose of the family is to maintain the well-being of its members and of society. Idea ...

of ''

Boreidae Boreidae, commonly called snow scorpionflies, or in the British Isles, snow fleas (no relation to the snow flea '' Hypogastrura nivicola'') are a very small family of scorpionflies, containing only around 30 species, all of which are boreal or ...

''. Its common name is snow flea. It has stubby, grey-brown wings with a metallic sheen. Snow fleas crawl or hop over the snow at temperatures around

freezing point The melting point (or, rarely, liquefaction point) of a substance is the temperature at which it changes state from solid to liquid. At the melting point the solid and liquid phase exist in equilibrium. The melting point of a substance depend ...

and thus resemble glacier fleas and snow flies. The males have 4 short, wing vestiges which curve downwards at their ends. The females only have two scale-like wing vestiges. In general, the female may be recognised from a curved, sabre-like pipe that acts as an ovipositor. In their fully formed state, these animals are only found in the colder period of the year between October and March. During this time mating takes place. The larvae live on moss-covered areas and withdraw in September into holes in the group to pupate.

Sources

* * Alfred Edmund Brehm: ''Däggdjurens Lif.'' Em. Girons, Stockholm 1882, pp. 145f. (Swedish
(online at: ''runeberg.org'')
* Döderlein: ''Bestimmungsbuch für deutsche Land- und Süsswassertiere/ Insekten.'' Part I: ''Käfer, Wespen, Libellen, Heuschrecken usw.'' Oldenbourg, Munich, 1932, DNB 365535060, p. 78. {{Taxonbar, from=Q573384 Boreus Insects described in 1767 Taxa named by Carl Linnaeus