Belonging to the order Homoptera, or plant suckers, cicadas are relatives of the aphids and leafhoppers. Cicadas are the loudest singing insects in the world. They are also the most efficient singers, using less energy to create song than the crickets and katydids. Cicadas are a prominent component of the late summer insect symphony in North America, and may be heard singing from mid-morning until dusk. Learn the songs of the following tweleve common species and you'll be able to identify most of the piercing buzzes and pulsating trills coming from high in the trees (and sometimes from shrubs). Your friends will be impressed. NOTE: 17-year Periodical Cicada is covered separately.