Mecoptera (Scorpionflies and Snow Fleas) Identification

There are four species of mecopterans found in the British Isles. These are the Scorpionflies (family Panorpidae): Panorpa communis, Panorpa germanica, and Panorpa cognata; and the Snow Fleas (family Boreidae): Boreus hyemalis.

Panorpidae (Scorpionflies)

The three species of Scorpionflies can easily be identified from the males, in the field or from photographs, by looking at the structure of the swollen genital capsule (found at the end of the abdomen, held over the body like a Scorpion’s sting). On the genital capsule (see image below) are features called callipers (or hypovalves), that are different shapes for each of the species.

Male Scorpionfly (Panorpa germanica) showing enlarged genital capsule and location of callipers

Identification of the three species are given below

Unfortunately females need to be dissected to identify their species. This involves examining the shape of the ovipositor, which sits in the abdomen and needs to be extracted. Identification of the different species are given below.

It may be possible to identify species from the patterns on their wings, however more work is required to make sure that this gives accurate identification.

Panorpa vulgaris

There could potentially be another Scorpionfly species present in the British Isles, this is Panorpa vulgaris. This species has the same structure of callipers as Panorpa communis, however it differs in its wing pattern. Panorpa vulgaris has a large basal spot that covers two cells on the wing (see image below, highlighted by red circle), whereas Panorpa communis has a small basal spot that covers only one cell.

Panorpa vulgaris showing similar calliper structure as Panorpa communis and large basal spot on wing. (Image J. Van Duinen)

If you think you have found an example of Panorpa vulgaris please send images/specimen to us for confirmation.

Boreidae (Snow Fleas)

There is only one species of Snow Flea in the British Isles, this is Boreus hyemalis. It is a very distinctive looking insect that is easy to identify. The adults are also active in the Winter months, generally in upland mossy areas. If there has been snowfall you can often find them walking over the snow surface.

They are small insects (approx. 5 mm), with an elongated face, the wings are reduced (to spines in males, and very small, difficult to see in females), females have a distinctive ovipositor.

Boreus hyemalis Male (image: G.S. Martin (CC BY-SA 2.0)) and Female (image: G.S. Martin (CC BY-SA 2.0)) showing distinctive features