typical treehoppers

Membracidae is a large family of true bugs known as treehoppers. There are two families of treehoppers, and Membracidae is by far the largest and most widespread. They occur worldwide, on every continent except Antarctica. There are about 3,500 species of Membracidae in about 430 genera in 9 subfamilies worldwide, 266 species in about 60 genera in 5 subfamilies in North America north of Mexico, and at least 73 species in at least 22 genera in 3 subfamilies in Minnesota.

Though called treehoppers, Membracidae occur on all types of vegetation. Most adults feed on the sap of trees or shrubs, but some feed on weeds or grasses, especially as nymphs. Many are host specific, feeding on plants in a single genus or family. Others are generalist feeders (polyphagous). Most are solitary but some are subsocial and appear in groups.

The female has a saw-like ovipositor. She uses it to cut a slit in a twig and deposits an egg in the slit. The twig usually dies beyond that point.

Adults and nymphs exude a sugary substance called honeydew, which could otherwise be infected with sooty molds. Ants, bees, and wasps feed on honeydew, and treehoppers are sometimes protected from predators by ants.

Adults are small, usually ½″ (12 mm) or less in length. The exoskeletal plate covering the thorax (pronotum) is very long, extending back over the abdomen, and sometimes extending forward over the head, helmet-like. It is often expanded into an unusual shape. On some it is rounded, and the treehopper appears hump-backed. On some it projects upward and forward, looking like a plant thorn. On some it is spined, is keeled, or has a horn.

The wings are held roof-like over the body when at rest.

Sources

24, 27, 29, 30, 82.