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324 etc.). The group includes two cosmopolitan pests, the pea weevil, Bruchus pisorum, which feeds on growing, though not stored (i.e., dried) peas, and the bean weevil, Acanthoscelides obtectus (Figure 10.19B), which eats both beans and peas, either in the field or in storage. On the other hand, two Mexican species of Acanthoscelides have been imported into Australia for the biological control of the giant sensitive plant, Mimosa pigra. Some 35,000 species of CHRYSOMELIDAE (leaf beetles) have been described. Adults are frequently brightly colored beetles that feed on foliage and flowers. The larvae are varied in their habits. They may feed exposed on leaves or stems, or mine into them. Some live below ground and feed on roots. Others live in ant nests and a few are aquatic. The family includes a large number of pest species, perhaps the most infamous of which is the Colorado potato beetle, Leptinotarsa decemlineata (Figure 10.19C), belonging to the subfamily CHRYSOMELINAE. Most pest species, however, are in the subfamilies GALERUCINAE and ALTICINAE. For example, Acalymma vittata, the striped cucumber beetle, feeds in the adult stage on a variety of cucurbits and, as a larva, on the roots of various plants. This species is known to act as a vector of certain diseases that cause wilting. Flea beetles (Alticinae), so-called because of their jumping ability, attack a variety of crops, for example, canola, mustard and turnip (Phyllotreta spp.), and tobacco, potato, tomato, and eggplant (Epitrix spp.) (Figure 10.19D). Conversely, some species are important biological control agents for weeds; for example, Longitarsus jacobaeae (from southern Europe) for ragwort (Senecio jacobaea) in Australia, and Agasicles hygrophila (from Argentina) for alligator weed (Alternanthera philoxeroides) in Australia and the United States.

Superfamily Curculionoidea

Most adult Curculionoidea are easily recognized by the prolongation of the head to form a rostrum at the tip of which are located the mouthparts. It is estimated that the superfamily already includes more than 57,000 described species, about 50,000 of which belong to the family CURCULIONIDAE (weevils, snout beetles) (Figure 10.20A). Arrangement of this vast number of species into subfamilies and taxa of lower rank is perhaps the major problem for coleopteran systematists at the present time. Some authorities recognize more than 100 subfamilies, though some of these are given family status by others. Almost all weevils are phytophagous, and all parts of plants are exploited. Adults bore into seeds, fruit, and other parts of plants. Larvae usually feed within plants or externally below ground. Not surprisingly, the group includes a very large number of pests, for example, the granary and rice weevils, Sitophilus (= Calandra)granarius and S. oryzae, respectively, which attack cereal seeds, peas, and beans, and various Anthonomus species, of which the best known is A. grandis, the boll weevil, which attacks cotton. Two subfamilies that require specific mention are the PLATYPODINAE (pinhole borers) and SCOLYTINAE (bark beetles, ambrosia beetles) (Figure 10.20B), both of which are frequently given the rank of family. Members of these two groups are woodborers and, unlike the majority of weevils, adults do not have a well-developed rostrum. In both subfamilies the beetles generally live beneath the bark of the tree where they construct a characteristic pattern of tunnels (Figure 10.20C). Many species attack healthy trees, which they girdle and kill. The beetles usually feed on fungi, which they cultivate in the tunnels. In North America Dutch elm disease is transmitted by the smaller European elm bark beetle, Scolytus multistriatus, introduced into the United States around the 1900s, and by the native elm bark beetle, Hylurgopinus rufipes.

The ANTHRIBIDAE (2600 species) form a mainly tropical family, most species of which are found in rotting wood or fungi, though a few feed on seeds, etc., including the

FIGURE 10.20. Curculionoidea. (A) The rose curculio, Rhynchites bicolor (Curculionidae); (B) the shothole borer, Scolytus rugulosus (Curculionidae); and (C) boring pattern of S. rugulosus [A, B, from E. S. Dillon and L. S. Dillon, 1972, A Manual of Common Beetles of Eastern N. America. By permission of Dover Publications, New York. C, from L. A. Swan and C. S. Papp, 1972, The Common Insects of North America. Copyright 1972 by L. A. Swan and C. S. Papp. Reprinted by permission of Harper & Row Publishers, Inc.]

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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