Shieldbugs are true bugs belonging to the order Hemiptera and they have piercing mouth parts, known as a rostrum, for sucking the juices from either plants or animals depending on the species. The adults have two pairs of wings with the forewings usually hardened.

Shieldbugs derive their name from the shield-like shape of the adult. The insect usually overwinters as the adult and becomes active in spring and the female then lays her eggs. The larvae or nymphs go through several instars before they complete their metamorphosis to the adult stage and have the ability to fly. Some twenty species of Shieldbugs and the closely related Squashbugs are found in Ireland.