HARLEQUIN CABBAGE BUG

(Murgantia histrionica), insect belonging to the stinkbug family (Pentatomidae) of the order Heteroptera. Though of tropical or subtropical origin this insect now ranges from the Atlantic Ocean to the Pacific Ocean in North America. Shield-shaped, about 1.25 centimetres (0.5 inch) long, and brilliantly coloured with red, yellow, and black, the harlequin bug sucks sap and chlorophyll from crops such as cabbage, causing them to wilt and die. Fifty to 60 adult harlequin bugs may simultaneously feed on one large plant. The barrel-shaped white eggs, ringed with black, are laid in double rows of 12 on the underside of leaves. Within a month the eggs hatch, and the active young, which resemble the adult except that they are wingless, molt five times. In warm climates there may be three or four generations annually; the adults may live several months. Removal of host plants when a crop is harvested and the use of trap crops such as mustard, on which the bugs concentrate in the spring and can subsequently be killed by insecticides, reduce losses of cabbage, Brussels sprouts, turnips, and related crops. This insect pest is sometimes known as calico back, terrapin back, firebug, and harlequin bug. The name harlequin bug has been used in South America for a longhorn beetle (Acrocinus longimanus). In Australia an insect (Dindymus versicolor) of the order Heteroptera, injurious to apples and other fruits, is called the harlequin fruit bug.