The bed bugs are wingless, reddish-brown arthropods, with a flat, oval body. The pronotum of the thorax extends laterally as a thin rim. In Cimex hemipterus the width of pronotum is two times the length at midline. This species is more common in tropical areas. Bed bugs have become closely associated with humans and are found very widely throughout the world. They also occur in poultry houses.