FIGURES 52-53 (52) Paederus cruenticollis (Staphylinidae) exhibiting warning coloration observed in many species of this genus. (Image provided by copyright holder, CSIRO Entomology, Canberra, ACT, Australia.) (53) Dermatitis linearis on human forearm at 66 h after an adult Paederus beetle had been crushed on volunteer's skin. (Photograph courtesy J. Howard Frank.)

Hercules beetles (Scarabaeidae) is a traditional source of entertainment. With a referee controlling the action, two males are introduced into an arena. When a female is placed nearby, her mating pheromones trigger the combatants to engage each other. The match ends and a victor is declared when one male becomes exhausted or backs down from the advances of his opponent. In Central America local craftsmen blur the distinction between "pet" and "jewelry" by gluing rhinestones, glass beads, and a small chain to the dorsal surface of zopherid beetles. When the tiny chain is pinned to clothing, the tethered beetle becomes living jewelry.

Entomophagy, the eating of insects, is common in many parts of the world, and beetles often make up part of the menu. Larvae of palm weevils (Curculionidae) are considered to be a delicacy on the islands of the South Pacific. Similarly the fleshy, sausagelike larvae of various long-horned beetles (Cerambycidae) and scarabs are relished by people around the world. Mealworms, the larvae of some tenebrionid beetles, are easily reared and have become standard fare for culinary demonstrations of entomophagy.

Beetles attract the most attention when they become economic pests of agriculture, horticulture, and forestry. Two families, the snout beetles (Curculionidae) and the leaf beetles (Chrysomelidae), include many serious pest species. In the middle to late 1800s, the Colorado potato beetle, Leptinotarsa decimlineata (Chrysomelidae) abruptly expanded its range across North America and then colonized Europe and neighboring regions. Great efforts were made to thwart the invader each time it appeared, but ultimately the beetles succeeded. Throughout the 20th century an epic battle was waged against the notorious boll weevil, Anthonomus grandis grandis (Curculionidae), in the Cotton Belt of the southern United States, where it inflicted great financial losses. A sustained and coordinated effort to control this pest succeeded in eradicating the boll weevil from portions of several states by the turn of the millennium.

Predaceous ladybugs are often used in biological control to suppress populations of homopterous crop pests (i.e.,

FIGURE 54 The jewel scarab, Chrysina cusuquensis, known only from a restricted fragment of forest in northern Guatemala. (Photograph courtesy of David Hawks.)

aphids and scales). In the first successful biological control introduction, an Australian ladybug, Rodalia cardinalis, suppressed the cottony cushion scale (Hemiptera) on citrus crops in California. Phytophagous beetles have been employed to control weeds. In the 1960s the cattle-rearing industry in Australia faced a dilemma: because cows are not native to the continent, no natural bovine dung entomofauna was available to use their feces. Therefore cow patties persisted for months, during which time they served as breeding grounds for pestiferous horn flies. After careful study, Australian entomologists introduced South African Onthophagus dung beetles (Scarabaeidae). The measure was successful, and the problem quickly abated.

Perhaps the least appreciated human—beetle interactions are those in which human population pressure inflicts a negative impact on beetle populations. Coleopteran diversity is largely attributable to their specialization for particular geographic locales, microhabitats, and food. As human populations grow and people alter the Earth for their needs, destruction of spatially restricted resources is an inevitable result, leading to extinction of species associated with those resources. Ironically, a characteristic that helped Coleoptera to attain the astounding degree of diversity that it exhibits today also predisposes many beetle species to anthropogenic extinction (Fig. 54).

See Also the Following Articles

Boll Weevil • Cultural Entomology • Dung Beetles • Hymenoptera • Japanese Beetle • June Beetles • Ladybugs

Further Reading

Arnett, R. H., Jr., and Thomas, M. C. (eds.). (2001). "American Beetles."

Vol. 1. CRC Press, Boca Raton, FL. Arnett, R. H., Jr., Thomas, M. C. Skelley, P. E., and Frank, J. H. (2002).

"American Beetles." Vol. 2. CRC Press, Boca Raton, FL. Beutel, R. G., and Haas, F. (2000). Phylogenetic relationships of the suborders of Coleoptera (Insecta). Cladistics 16, 103—141. Branham, M. A., and Wenzel, J. W. (2001). The evolution of bioluminescence in cantharoids (Coleoptera: Elateroidea). Fla. Entomol. 84, 565—586. Carpenter, F. M. (1992). Arthropoda 4. In "Treatise on Invertebrate Paleontology," Part R (R. L. Kaesler, ed.). Geological Society of America, Boulder, CO, and University of Kansas, Lawrence. Choe, J. C., and Crespi, B. J. (eds.). (1997). "The Evolution of Social Behavior in Insects and Arthropods." Cambridge University Press, Cambridge, U.K.

Crowson, R. A. (1981). "The Biology of Coleoptera." Academic Press, London.

Elias, S. A. (1994). "Quaternary Insects and Their Environments."

Smithsonian Institution Press, Washington, DC. Evans, A. V., and Bellamy, C. L. (1996). "An Inordinate Fondness for

Beetles." Holt, New York. Farrell, B. D. (1998). "Inordinate fondness" explained: Why are there so many beetles? Science 281, 555—559. Lawrence, J. F. (1989). Mycophagy in the Coleoptera: Feeding strategies and morphological adaptations. In "Insect—Fungus Interactions" (N. Wilding, N. M. Collins, P. M. Hammond, and J. F. Webber, eds.), pp. 1—23. Academic Press, London. Lawrence, J. F. (1991). Order Coleoptera. In "Immature Insects." Vol. 2 (F.

W. Stehr, ed.), pp. 144-658. Kendall/Hunt, Dubuque, IA. Lawrence, J. F., and Britton, E. B. (1994). "Australian Beetles." Melbourne

University Press, Melbourne, Australia. Lawrence, J. F., Hastings, A. M., Dallwitz, M. J., Paine, T. A., and Zurcher, E. J. (2000). Beetles of the World (CD-ROM, Windows version). CSIRO Publishing, Victoria, Australia. Lawrence, J. F., Hastings, A. M., Dallwitz, M. J., Paine T. A., and Zurcher, E. J. (2000). Beetle Larvae of the World (CD-ROM, Windows version). CSIRO Publishing, Victoria, Australia. McCormick, J. P., and Carrel, J. E. (1997). Cantharidin biosynthesis and function in meloid beetles. In "Pheromone Biochemistry" (G. D. Prestwich and G. J. Blomquist, eds.), pp. 307-350. Academic Press, London.

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