The Hemipteroid Orders

Adults are active, hopping insects that in many cases bear a crude resemblance to a frog, hence the common name of froghopper. Aphrophoridae, with 1300 species, form the largest family with a wide distribution. Its members are usually found on herbaceous plants, but a few live on trees to which they sometimes do considerable damage. Cercopidae (1000 species) are also widespread but particularly common in the tropics. A few species are pests of grasses and clovers, for example, Philaenus spumarius, the meadow spittlebug (Figure 8.11). Machaerotidae (100 species) are restricted to Asia, tropical Africa, and Australia.

Superfamily Cicadoidea

Cicadas are common insects in all of the warmer regions of the world. They are generally between 2 and 5 cm in length and are particularly well known because of their sound-producing abilities and the length of time required for juvenile development. Virtually all of the 1500 or so species are placed in the family CICADIDAE. The sound-producing organs (tymbals) are located on the dorsal side of the first abdominal segment of males only. The auditory tympana are better developed in males than females and are found on the ventral side of the anterior abdominal segments. Most cicadas require several years for juvenile development. A well-known periodic cicada is Magicicada septendecim (Figure 8.12), which, in the eastern United States, requires 17 years for its development; in contrast, the southern form takes only 13 years to mature. A larva spends this entire period underground, feeding on roots, especially those of perennial plants. Prior to the final molt the larva leaves the soil to complete its metamorphosis on a tree or other object. Eggs are laid in twigs, a process that may cause considerable dieback of the tree.

FIGURE 8.13. Cicadelloidea. (A) The beet leafhopper, Circulifer tenellus (Cicadellidae); (B) the potato leafhop-per, Empoascafabae (Cicadellidae); and (C) the buffalo treehopper, Stictocephala bubalus (Membracidae). [A, B, from D. M. Delong, 1948, The leafhoppers, or Cicadellidae, of Illinois, Bull. Ill. Nat. Hist. Surv. 24(2):97-376. By permission of the Illinois Natural History Survey. C, from D. J. Borror, D. M. Delong, and C. A. Triplehorn, 1976, An Introduction to the Study of Insects, 4th ed. By permission of Brooks/Cole, a division of Thomson Learning.]

FIGURE 8.13. Cicadelloidea. (A) The beet leafhopper, Circulifer tenellus (Cicadellidae); (B) the potato leafhop-per, Empoascafabae (Cicadellidae); and (C) the buffalo treehopper, Stictocephala bubalus (Membracidae). [A, B, from D. M. Delong, 1948, The leafhoppers, or Cicadellidae, of Illinois, Bull. Ill. Nat. Hist. Surv. 24(2):97-376. By permission of the Illinois Natural History Survey. C, from D. J. Borror, D. M. Delong, and C. A. Triplehorn, 1976, An Introduction to the Study of Insects, 4th ed. By permission of Brooks/Cole, a division of Thomson Learning.]

Superfamily Cicadelloidea

Most of the Cicadelloidea are placed in two very large families, CICADELLIDAE (JAS-SIDAE) (leafhoppers) and MEMBRACIDAE (treehoppers). The cosmopolitan Cicadellidae (20,000 species), which form the largest homopteran family, are found on almost all types of plants. They rank second only to the Aphididae in the enormity of their numbers and, in consequence, are major pests. They cause a wide variety of injuries to plants. They may remove large quantities of sap, block the phloem tubes, or destroy the chlorophyll so that growth is stunted. Many are vectors of viruses that cause disease. A few damage the plants by their oviposition habits. Two well-known pests are Circulifer tenellus, the beet leafhopper (Figure 8.13A), and Empoascafabae, the potato leafhopper (Figure 8.13B), which feeds on solanaceous plants, beans, celery, alfalfa, and various flowers. Several other species of Empoasca are also important pests (see Swan and Papp, 1972). Membracidae (2400 species) are easily recognized by their enormous pronotum that projects backward over the abdomen and often assumes bizarre shapes. The family is primarily neotropical, They are generally gregarious and attended by ants for the honeydew they produce. They are seldom of economic importance; however, Stictocephala bubalus, the buffalo treehopper (Figure 8.13C), may damage young fruit trees and nursery stock as a result of its egg-laying activity.

Suborder Heteroptera

In Heteroptera the head is usually prognathous, almost always with a gula; the pronotum is well developed; and fore wings when present are in the form of hemelytra, with wings held flat over the body when at rest.

Infraorder Coleorrhyncha Superfamily Peloridioidea

Contained in this superfamily is a single, Southern Hemisphere family, PELORIDI-IDAE, whose 25 species are small, flattened, cryptically colored Hemiptera found among moss and liverworts or in caves, The family is all that remains of a formerly numerous and 223

widespread Northern Hemisphere group, with fossils from as early as the Lower Jurassic period, Their current distribution is disjunct, with species occurring in South America and the Australian region. Peloridiids have a fascinating mixture of homopteran and heteropteran features, as well as such ancestral characters as the complete tentorium, discrete pro- and mesothoracic ganglia, and eight pairs of abdominal spiracles.

Beekeeping for Beginners

Beekeeping for Beginners

The information in this book is useful to anyone wanting to start beekeeping as a hobby or a business. It was written for beginners. Those who have never looked into beekeeping, may not understand the meaning of the terminology used by people in the industry. We have tried to overcome the problem by giving explanations. We want you to be able to use this book as a guide in to beekeeping.

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