Homoptera

Homoptera is a historic and informal term used to refer to a diverse group of sap-feeding insects within the order Hemiptera. Included are aphids, scale insects, whiteflies, mealybugs, psyllids, cicadas, leafhoppers, and planthoppers. Members share piercing-sucking mouthparts and typically feed on plant sap, but wing forms, lifestyles, and degrees of mobility vary widely. The name suggests uniform wings, a characteristic that is not consistent across all groups.

In modern entomology, Homoptera is not recognized as a valid taxon because it is paraphyletic with respect to other Hemiptera groups. Current classifications place these insects in two major suborders of Hemiptera: Sternorrhyncha, which includes aphids, scales, whiteflies, psyllids, and mealybugs; and Auchenorrhyncha, which includes cicadas, planthoppers, leafhoppers, and treehoppers. Heteroptera remains the other major subdivision of Hemiptera. As such, the term is largely historical and used mainly for convenience in non-technical contexts.

Morphology and life history vary among Homoptera. Most possess siphoning mouthparts adapted for feeding on phloem or xylem, with life cycles ranging from simple to complex. Aphids, for example, can reproduce by parthenogenesis and exhibit rapid population growth and host alternation, while scale insects often have sessile adult females. Cicadas and planthoppers typically have longer nymphal stages and distinct seasonal patterns.

Ecology and economic importance are notable: many homopterans are agricultural pests and vectors of plant pathogens, causing crop losses through feeding and honeydew production. Management focuses on integrated approaches that emphasize natural enemies, cultural practices, and careful pesticide use to minimize resistance and ecological disruption.