The brassica shieldbug has several common names, including crucifer shieldbug and cabbage bug. These all make reference to the bug's foodplants. It favours plants from the cabbage and mustard family, Brassicaceae, often known as brassicas or crucifers. It can often be found on garlic mustard or horse-radish. On sunny spring days, you can find brassica shieldbugs in groups on the leaves of suitable plants. Like most shieldbugs, nymphs hatch in spring or early summer and are fully grown by autumn, ready to spend the winter as an adult.
How to identify
Black with a deep, blue or green metallic sheen. It is marked with a border around the body, a line down the centre of the pronotum (the section behind the head) and three spots on the back, near the end of the body. These markings can be red, white or yellow.
Distribution
Well distrubuted across southern and central England, though scarcer in the southwest. Patchily distributed in Wales, mainly in the east, and in Yorkshire. Like many bugs, it appears to be spreading.
Did you know?
Studies have shown that brassica shieldbugs use their antennae to detect the chemicals emitted by their favourite plants, helping them track down a suitable food source.
