Widespread in England, Wales and Ireland and belonging to the order Hemiptera.
In Britain the Shield Bugs are represented by four different families; Cydnidae, Acanthosomatidae, Pentatomidae and Scutelleridae. Generally they are a true bug with a green and chestnut-brown, flattish oval or shield shaped behind the thorax (hence their common names), the distinctly triangular shape and the bright green scutellum or shield. The latter is surronded by a bold red triangle formed by the forewings and the rear of the pronotum. and the fact that their antennae are comprised of five elements each, It's wings are pale and membranous at the tip. Like a beetle, it folds its wings across its back. Its young nymph is similar in appearance but brownish bronze in colour without wings. It is most commonly found on hedges.
Length 13mm to 16mm.
The Hawthorn Shield Bug is relatively easy to find and is a good example of a typical 'Shield Bug'. It is to be found on a number of tree and shrub species, often on hawthorn after which it is named. Shield bugs are mainly phytophagous (feeding on plant sap), though a few are carnivorous and may even be useful in controlling pests (see below). They are often called Stink-Bugs because they can produce a horrible smell. In the adults the noxiously smelling fluid is produced by a pair of glands in the thorax and released via a pair of pits on the metathorax, in the nymphs there are 3 pairs of scent glands in the abdomen and the liquid is released through special openings in between the 3/4, the 4/5 and the 5/6 abdominal segments. The scent does work though and is known to repel certain vertebrate predators, in some species it will strongly stain your fingers like iodine.
Feeds mainly on hawthorn berries and consequently seldom found where this shrub is absent. Also feeds on leaves of other deciduous trees when berries not available and it will also feed on White Beam and Oak.
It favours hedgerows and woods. Autumn adults hibernate in crevices in trees or under pieces of bark or in grass tussocks and emerge again April-July. The eggs are laid on leaves in batches of up to 24, the nymphs hatch shortly and look very much like miniature adults in June-August.
