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short, contiguous. No Y-vein in anal area of FW. Usually 2 ocelli

(3 in cicadas). Jumping insects (except cicadas).

CICADAS Family Cicadidae See also PL 4

Identification: Large insects, mostly 1-2 in. FW membranous. 3 ocelli, d* usually with sound-producing organs at base of abdomen on ventral side. Nonjumping insects.

Cicadas are common insects, but are more often heard than seen since the majority are arboreal. Song is produced only by males, and is usually a loud (sometimes pulsating) buzz. Most cicadas are large blackish insects, often with greenish markings, that appear each year in July and August; their life cycle lasts 2-5 or more years, but the broods overlap and adults are present each year. The periodical cicadas (Magicicada) have a life cycle of 13 or 17 years, and adults are present in a given area only in certain years. These cicadas occur in the East, and adults appear in May and June; they are 19-33 mm. and have the eyes and wing veins reddish. The 17-year cicadas (3 species) are principally northern. The 13-year cicadas (3 species) are principally southern. The species in each life-cycle group differ in size, color, and song; most emerging broods of periodical cicadas contain 2 or 3 species. Eggs are laid in twigs, which usually die and break off; nymphs live in the ground and feed on roots. Nymphs are stout-bodied, brownish, with expanded front tibiae; they usually crawl up on a tree trunk for their molt to the adult. Cicadas are generally of little economic importance,

but the egg laying of large numbers of periodical cicadas often causes serious damage to young trees.

TREEHOPPERS Family Membracidae Identification: Small jumping insects, usually 12 mm. or less. Pronotum prolonged backward over abdomen.

Treehoppers are common insects occurring on all types of vegetation. They vary in shape, owing to variations in shape of the pronotum; most of them appear humpbacked and some are shaped like thorns. Adults of most species feed on trees and shrubs, but some feed on weeds and grasses, especially in the nymphal stage. Eggs are usually laid in twigs, and the terminal portion of such twigs generally dies.

FROGHOPPERS and SPITTLEBUGS Family Cercopidae Identification: Small jumping insects, generally less than 12 mm. Pronotum does not extend back over abdomen. Hind tibiae with 1 or 2 stout spines, and usually a circlet of spines at apex.

Adults are called froghoppers because many are somewhat wider posteriorly and are shaped rather like tiny frogs; nymphs produce and become surrounded by a spittlelike mass, and are called spittlebugs. These insects are very common, and spittle masses are often abundant on grass and weeds; a few spittlebugs feed on trees. One of the most common species is the Meadow Spittlebug, Philaenus spumarius (Linn.), which varies considerably in color but is usually brownish; it often causes considerable damage to clovers.

LEAFHOPPERS Family Cicadellidae See also Pl. 4

Identification: Similar to Cercopidae but body usually tapers posteriorly or is parallel-sided, and hind tibiae have 1 or more rows of small spines.

This is a very large group; many species are common and abundant insects. Most of them are less than 10 mm., and many are brightly colored. They occur on a diversity of plants but each species is usually rather specific in its selection of a food plant. Many are serious pests of cultivated plants, causing injury by their feeding, and a few serve as vectors of plant diseases. Leafhoppers often discharge from the anus a clear watery fluid called honeydew, to which other insects (particularly ants) may be attracted.

Planthoppers: Superfamily Fulgoroidea

Antennae rise on sides of head beneath eyes. Middle coxae elongate and separated. Two anal veins in FW usually meet distally to form a Y-vein. Jumping insects, mostly 10 mm. or less. Many species have very short wings that cover only the basal abdominal segments. Both short- and long-winged individuals occur in some species. There is usually a distinct angle between the front (or dorsal) and lateral surfaces of the head; antennae, eyes, and lateral ocelli are on the lateral surface. Planthoppers constitute a large group but are seldom as abundant as other hoppers.

The N. American families of planthoppers may be divided into 2 groups on the basis of the structure of the 2nd segment of the hind tarsus: (1) this segment small to minute, its apex rounded and with a small spine on each side: Tropiduchidae, Acanaloniidae,

Head and beak of Froghopper

Head and beak of Planthopper coxa coxa

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