Snake-flies, alderflies, lacewings and scorpion flies in Essex
Order MECOPTERA
The Mecoptera are only distantly related to the Neuropterida but have, traditionally, been considered
together. In Britain they are represented by just four species in two families, each containing a single
genus. A fifth species, Panorpa vulgaris, is a thermophilic insect of southern and central Europe
and is a likely candidate for colonisation of Britain if climate warming continues.
Family BOREIDAE - the Snow-flea
The Boreidae are represented in Britain by one species, the Snow flea. A sexually dimorphic species,
the females have vestigial wings whilst those of the male are modified into stout spines held over the
body; these spines, which are serrated on the inner face, support the female which rides on the back
of the male during mating. The Snow-flea is unusual amongst British insects in that it is active
during winter, being found from about November to February,
Boreus hyemalis (Linnaeus, 1767)
National status: Local (Local)
Predicted county status: Rare/-
Dis tribution
There are old records from Epping Forest, made
during 1927 and 1928. Other than these, the only
Essex record is of one in a pitfall trap at Lodge
Road Bog, Epping Forest, during December 1990
(Peter Harvey). Although the species is
apparently rare in Essex, its seasonality almost
certainly renders it very under-recorded; winter
pitfall trapping amongst moss communities may
provide further records.
Habitat and ecology
Most British records are from heathland or
moorland, but there is a significant population in
the Home Counties area where these habitats are
absent. Eggs are laid amongst moss, on the ground, on walls or on logs and the moss is probably the
key to the distribution rather than anything else. British literature is somewhat lacking in information,
however; Fraser (1959) mentions Polytrichum commune, but this appears to be the only moss
mentioned in print. The Lodge Road record can be linked by association to Polytrichum and/or
Sphagnum.
Threats
The loss of moss communities, particularly Sphagnum-based communities, is a probable threat.
Etymology
From the Latin hiems - winter, hence hiemalis, meaning of the winter and a reference to the seasonality
of the species. The word has been anglicised to hyemalis.
Family PANORPIDAE - the scorpion flies
Although the individual species can only be separated by examination of the genitalia (Plant 1991b),
the genus is immediately recognisable in the field. The vernacular name relates to the appearance of
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Essex Naturalist (New Series) 17 (2000)