Membracoidea

Membracoidea can be distinguished from other Hemiptera superfamilies by the combination of an incomplete tentorium, enlarged midcoxae, and tibial setal rows. Within the superfamily, families are readily separated: Membracidae by the expanded pronotum covering most of the scutellum (except Centrotinae where scutellum is exposed); Cicadellidae by the unmodified pronotum, exposed scutellum, and characteristic head shape; Aetalionidae by intermediate pronotal expansion with exposed scutellum; Myerslopiidae by minute size, reduced wings, and litter-dwelling habits. The relict family Melizoderidae, restricted to South America, resembles small treehoppers with modest pronotal projections. Jascopidae (represented by Jascopus and Homopterulum) has uncertain placement but differs in having setal rows on all three pairs of tibiae rather than just mid and hind.

Membracoidea encompasses considerable morphological diversity across its constituent families. Leafhoppers (Cicadellidae) typically possess a flattened, streamlined body with a head narrower than the pronotum, enlarged hind femora adapted for jumping, and forewings held roof-like over the abdomen. Treehoppers (Membracidae) are distinguished by a dramatically expanded pronotum that often projects into bizarre shapes—thorns, buds, or other plant-like forms—frequently covering the scutellum and much of the wings. The smaller families exhibit more conservative morphology: Aetalionidae resemble modestly ornamented treehoppers, while Myerslopiidae are minute, litter-dwelling insects with reduced wings. All families share the diagnostic superfamily characters: incomplete tentorium (internal head skeleton), enlarged midcoxae, and setal rows on the mid and hind tibiae.

Membracoidea occupies virtually all terrestrial habitats supporting vascular plants. Leafhoppers are predominantly associated with herbaceous vegetation, grasses, and deciduous trees, with many species restricted to specific host plants. Treehoppers occur on woody plants, with strong preferences for particular host species; many form mutualistic associations with ants on host plants. Myerslopiidae are exceptional, inhabiting the litter layer of temperate forests and shrub bogs where they feed on roots and creeping stems. The superfamily spans elevations from sea level to high montane regions, with greatest species diversity in tropical lowland and montane forests.

Worldwide in distribution, with centers of diversity in the Neotropical region (Central and South America). The Neotropics harbor the greatest radiation of treehoppers (Membracidae), with all but one subfamily (Centrotinae) restricted to the New World. Leafhoppers (Cicadellidae) are cosmopolitan. Myerslopiidae exhibits a disjunct distribution in southern South America and New Zealand. Melizoderidae is restricted to South America. The superfamily is absent only from Antarctica and the most extreme polar regions.

Activity patterns vary by latitude and habitat. In temperate regions, most species are active from late spring through autumn, with overwintering typically as eggs. Tropical species may be active year-round, with population peaks during wet seasons. Some leafhoppers are migratory, undertaking long-distance dispersal in response to host plant phenology or seasonal conditions. Adult longevity ranges from weeks to several months depending on species and climate.

All members are obligate phloem feeders, using piercing-sucking mouthparts to extract plant sap. Myerslopiidae feed on roots and creeping stems of angiosperms, with salivary sheaths terminating in vascular bundles and indirect evidence of phloem feeding. Most leafhoppers and treehoppers feed on above-ground plant parts: leaves, stems, and woody tissues. Many species exhibit strong host plant specificity, while others are generalists.

• Vascular plants (Tracheophyta) - obligateAll families feed on angiosperms; some also utilize gymnosperms.
• Ants (Formicidae) - mutualisticNumerous treehopper species, particularly in subfamily Smiliinae, form mutualisms with ants that defend them in exchange for honeydew.
• Dryinidae (Hymenoptera) - parasitizedLeafhoppers (especially Gyponini) are hosts for dryinid wasps.
• Prionomastix (Encyrtidae) - parasitizedEncyrtid wasps in this genus parasitize both treehoppers and leafhoppers.

Hemimetabolous development with egg, nymph, and adult stages. Eggs are typically inserted into plant tissue (leafhoppers) or deposited on host plants (treehoppers). Nymphs resemble adults but lack fully developed wings and reproductive structures; they undergo five instars before molting to adulthood. Development time varies from weeks in warm climates to months in temperate regions. Many temperate species produce a single generation annually; tropical species may have multiple overlapping generations. Overwintering stage varies: eggs in most temperate leafhoppers and treehoppers; adults in some species. Myerslopiidae nymphs and adults are both strong jumpers and actively disperse, as evidenced by capture in pan traps.

Jumping is the primary escape mechanism across all families, powered by enlarged hind femora. Many treehoppers exhibit complex social behaviors, including aggregation and maternal care of eggs and nymphs. Ant mutualism involves the production of honeydew (excreted excess plant sugars) that attracts and sustains attendant ants, which in turn defend treehoppers from predators and parasites. Some treehoppers communicate through substrate-borne vibrations transmitted through host plants. Males of many species produce species-specific courtship signals. Dispersal behaviors range from trivial local movements to long-distance migration in some leafhopper species.

As abundant phloem feeders, membracoids serve as significant herbivores transferring plant nutrients and energy to higher trophic levels. They are important prey for diverse predators including spiders, predatory insects, and birds. Their honeydew production supports ant populations and contributes to nutrient cycling via sooty mold growth. Many species function as vectors for plant pathogens, particularly leafhoppers transmitting phytoplasmas, viruses, and bacteria causing crop diseases. Their host plant specificity influences plant community composition and succession. The extraordinary morphological diversity of treehoppers, particularly pronotal modifications, represents a notable example of adaptive radiation in insect evolution.

Leafhoppers are economically significant agricultural and horticultural pests, directly damaging crops through feeding and indirectly transmitting plant pathogens. Major pest species include Empoasca fabae (potato leafhopper), Macrosteles quadrilineatus (aster leafhopper, vector of aster yellows), and Dalbulus maidis (corn leafhopper, vector of maize pathogens). Treehoppers generally have minor economic impact, though some species damage orchard and ornamental trees. The group has substantial scientific value for studying insect-plant coevolution, mutualism, adaptive radiation, and speciation. Treehoppers are popular among entomologists and naturalists for their extraordinary morphological diversity.

• Cicadoidea (cicadas)Also in infraorder Cicadomorpha with membracoid head structure and jumping nymphs, but distinguished by much larger size, prominent tymbal organs for sound production, and complete tentorium.
• Cercopoidea (froghoppers/spittlebugs)Related Auchenorrhyncha superfamily with jumping adults, but nymphs produce characteristic spittle masses; adults have different wing venation and head structure.
• Fulgoroidea (planthoppers)Often confused due to similar habits and some convergent morphologies, but distinguished by different head structure (often with elongated frons), carinate or modified pronotum, and different wing coupling mechanisms.

• phloem-feeding
• jumping
• ant-mutualism
• plant-pathogen-vector
• adaptive-radiation
• Neotropical-diversity-center

• BugGuide
• Wikipedia
• iNaturalist taxon
• NCBI Taxonomy
• Catalogue of Life
• Bizarre, beautiful extremes | Beetles In The Bush
• Observations on the Biology and Anatomy of Myerslopiidae (Hemiptera, Membracoidea)
• The first Archijassidae from the Middle Triassic of China (Hemiptera, Cicadomorpha, Membracoidea)
• A review of the encyrtid-wasp genus Prionomastix Mayr, 1876 (Hymenoptera, Encyrtidae), parasitoids of treehoppers and leafhoppers (Hemiptera, Membracoidea)
• Protocol for Membracidae inventory (Hemiptera, Auchenorrhyncha, Membracoidea): what are the ideal collection methods for the Atlantic Forest?
• Membracidae types (Hemiptera-Membracoidea) housed at the Museo de La Plata entomological collection (Argentina)
• Distributional patterns and possible origins of the tribes and genera of Coelidiinae (Homoptera, Membracoidea, Cicadellidae)
• Sexual association and cicadellid hosts of Dryinidae (Hymenoptera, Chrysidoidea): description of five new species from Brazil and a synopsis of the interaction with Gyponini (Hemiptera, Membracoidea)