Dock Bug Coreus marginatus

A speckled brown specialist that feeds exclusively on docks and sorrels—those bitter-tasting plants nobody else seems to want—this medium-sized bug (13-15 mm) is built tough for rugged living. Its broad abdomen and sturdy frame make it a survivor in hedgerows, wasteland, and overgrown patches from Europe across to North Africa and Asia. You'll spot it among dense vegetation wherever these humble plants thrive. It's one of nature's pickiest eaters, having found the perfect plant and sticking with it fiercely.