''Tritomegas bicolor'', the pied shield bug, is a species of shield bug found in Europe. The adult is black and white and 5.5–7 mm long. It is found across North Africa, Europe and Central Asia, although in the British Isles, it becomes rarer towards the north, and is absent from Scotland and Ireland. ''T. bicolor'' lives mainly on the ground, but is also visible on its host plants — chiefly ''Lamium'' and ''Ballota nigra''.