Shieldbugs

A Red-legged Shieldbug (Pentatoma rufipes) crawling amongst Sycamore seeds near QEII field at the beginning of August. It’s one of our larger shieldbugs at around 15mm long.

Bugs feed on plants and other invertebrates, sucking up the juices through their piercing, needle-like mouthparts. Shieldbugs, aptly named from their shape, are often associated with particular host plants, including bushes and trees, and a few will suck the fluids from small insects such as aphids. The Red-legged Shieldbug feeds on deciduous trees and shrubs like Sycamore.

This mating pair of Green Shieldbugs (each just over 10mm long) was at the QEII pond in June. Look out for them on Hawthorn and Bramble (as in this image) where they feed on unripe berries and seeds. The female lays small clusters of eggs, which hatch within a few weeks.

Green Shieldbug nymphs and egg cases

Shieldbug young (nymphs) go through five stages, each lasting just a week or more, before becoming winged adults.

Green Shieldbug 3rd instar nymph
in August by the canal

Green Shieldbug 5th instar nymph
in August by the canal

Some shieldbugs overwinter as adults, including the Green Shieldbug (though it morphs to a brown-bronze colour to better hide in leaf-litter), some, like the Red-legged Shieldbug, as third or fourth stage nymphs, and others (such as the Spiked Shieldbug, which feeds on caterpillars) will lay eggs in late summer which won’t hatch until early spring the next year.

There are around 50 types of Shieldbug and Leatherbug in the UK. The guides linked below describe the commoner species.

Further information and images

BBC Countryfile - British Shieldbug Guide: how to identify and where to see

The Woodland Trust - Shieldbug Identification: 10 common UK shieldbugs