The hawthorn shield bug (Acanthosoma haemorrhoidale) is a common European shield bug. Its chief food is haws, the fruit of the hawthorn tree, but adults can overwinter on a diet of leaves, and individuals can be found on many potential food plants, including pedunculate oak, sessile oak and whitebeam. They may grow up to 17 mm (0.67 in) long, and are camouflaged in shades of green and brown. Like many so-called "stink bugs", they may release unpleasant odours when disturbed.