Order Diplura - Two-pronged Bristletails

• Campodea and Japyx species

Small wingless insects, lacking eyes. Antennae long, with many segments. Mouthparts for biting. Tarsi are 1-segmented. Abdomen with a pair of jointed, filamentous cerci of variable length or with stout terminal pincers. Metamorphosis slight or wanting. Just over 400 known species, of which 12 are recorded in the British Isles.

Description. Mainly colourless, unpigmented insects, except for the darkened pincers in forms such as Japyx (b). Most species 2-5 mm long, except some Japyx spp. which may reach 50 mm in length.

Biology. Live in concealed, damp situations in the soil, under stones, in dead wood and among leaf litter, where they feed on decaying vegetable matter.

Distribution. Campodea spp. (a) are found in Britain and other temperate regions; Japyx spp. (b) are mainly tropical and sub-tropical, although some species occur in southern Europe.

Illustration: adapted from Imms 1957