Homopterans

Hemiptera, Homoptera. Wax bugs.

This suborder is a large one with many families, several of which are strictly Neotropical. Opinions differ as to its internal classification because of the diversity of basic body forms and extreme biological and anatomical adaptations. Some unifying characteristics are sucking mouthparts similar to those of heteropterans but with the elements usually consolidated into a short beak set so far back on the head as to appear to arise from behind the forelegs and piercing stylets often very long and coiled in the body when not in use. Wings, when present, are homogenous in texture, usually membranous but often thickened and fairly rigid and with few veins (although some have a reticulate pattern). There are two pairs of wings except for male scale insects, which have only the fore pair developed.

I use the name "wax bugs" to refer to the suborder because of the almost universal presence of wax-producing glands in its constituent families. These glands are variously developed on different parts of the body and always open exteriorly on the cuticle. Their secretions are extruded to the outside to take many forms for diverse functions, some well defined, such as the protective scale covering of armored scale insects, and others with unclear significance, such as the massive plumes trailing from the abdomen of some large fulgorids. Silk- and lac-producing glands are also present.

All are sap feeders and often very specific in their preferences for the sap of certain plants (Johnson and Foster 1986). They remove this fluid, sometimes in such quantity, because of enormous populations that may develop, that they kill or seriously injure their hosts. For this reason, and also because many are very efficient carriers of plant pathogens, wax bugs are plant pests of prime importance. Injurious species are found in almost all families but especially among the aphids, scale insects, and leafhoppers. Unlike their heteropteran relatives, no wax bugs have adapted to feeding on vertebrate blood or have become aquatic.

A mutualistic relationship exists between some hymenopterans and many wax bugs, especially aphids and scale insects (Letourneau and Choe 1987). The latter secrete "honeydew," a carbohydrate-rich overflow from the alimentary canal or integumentary glands which is greedily consumed and even specifically solicited, especially by ants. The ants attend the bugs, protecting them from predators, dispersing them, and even building shelters for them (Way 1953).

References

Johnson, L. K., and R. B. Foster. 1986. Associations of large Homoptera (Fulgoridae and Cicadidae) and trees in a tropical forest. Kans. Entomol. Soc.J. 59: 415-422. Letourneau, D. K., and J. C. Choe. 1987. Homopteran attendance by wasps and ants: The stochastic nature of interactions. Psyche 94: 81-91.

Way, J. T. 1953. Mutualism between ants and honeydew producing Homoptera. Ann. Rev. Entomol. 8: 307-344.

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