--- title: "Brazilian Treehopper (Bocydium globulare) | AnimalTracks.wiki" description: "A rainforest sap-drinker wearing a crown of glossy globes on slender horns, argued over by entomologists since 1903." image: "https://animaltracks.wiki/images/animals/brazilian-treehopper-1.webp" published: "2026-09-06" updated: "2026-09-19" --- # Brazilian Treehopper (*Bocydium globulare*) > **Status**: Checked against 3 sources, listed under Sources below. > **Tagline**: A rainforest sap-drinker wearing a crown of glossy globes on slender horns, argued over by entomologists since 1903. > **Soundtrack Vibe**: Organic Downtempo & Micro-Sampling // Bonobo, "Cirrus" > **Soundtrack Links**: [Spotify](https://open.spotify.com/track/2lJ4d8MCT6ZlDRHKJ1br14) | [YouTube](https://www.youtube.com/watch?v=WF34N4gJAKE) > **Vibe Match**: Complex micro-rhythmic textures and delicate chimes, assembled the way the crown is: a folded package under the old skin that unpacks into a finished structure in about 30 minutes at the last molt. ## Biological Superpowers & Stats - **Taxonomy**: *Bocydium globulare* - **Danger Level**: Low - **Conservation Status**: Not Evaluated ([IUCN Red List](https://www.iucnredlist.org/)) - **Superpower**: A globe-tipped pronotal crown that grows folded under the skin of the final nymph and unpacks itself in about half an hour at the last molt, for a function entomologists still call unknown. - **Habitat**: Tropical rainforest understory, recorded usually only a few feet above the ground on shrubs such as Miconia; its genus is known from Costa Rica and Trinidad south to Paraguay - **Diet**: Plant sap, taken from the undersides of leaves on shrubs such as Miconia - **Tags**: insect, bizarre-anatomy, herbivore, rainforest ## Natural History & Behavior Under a rainforest leaf, usually only a few feet off the ground, sits an insect wearing a crown that looks borrowed from another animal: dark, glossy globes held out on slender horns. The **Brazilian Treehopper** (*Bocydium globulare*) feeds on the undersides of leaves, and the headgear has been argued over since 1903 with nobody settling what it does. > **A Question Nobody Has Closed.** The entomologists who reviewed its genus in 1999 put it plainly: "the actual function of the peculiar pronotal structures is unknown, as are the life histories of many of the species." ## A Guess From 1903, Still Untested The crown is an outgrowth of the pronotum, the hardened plate that caps an insect's first chest segment. In 1903 the entomologist Poulton suggested the shape might mimic Neotropical seeds or small, spiny fruit, the sort of thing a hungry bird would rather not bite. Nobody has tested whether it fools a predator. A 2025 study lists camouflage, mimicry, warning colour and physical defence among the jobs proposed for a treehopper's pronotum, and says "there is currently little experimental evidence addressing these hypotheses." ## Unpacked in Half an Hour Whatever the crown is for, it is built in a hurry. Researchers in Costa Rica collected late-stage nymphs, carried them back to a hotel room and filmed the final molt. A *Bocydium* went from a densely folded package under its old skin to a finished crown in roughly 30 minutes. In a related treehopper the same transformation took about 35 minutes, and the team concluded it "likely occurs by pumping hemolymph (body fluid)" into ridges inside the structure, the way an insect pumps up a fresh pair of wings. Growing new cells would be far too slow to shape anything that fast. ## Life a Few Feet Off the Ground The 1999 revision of its genus gives no measurement for *B. globulare* by itself. It diagnoses the genus as a whole, 15 species of *Bocydium*, at a total length of 4.6 to 7.5 millimeters, roughly the size of a match head. Field notes from 1925 record that this species "usually occurs only a few feet above the ground, feeding on the undersides of leaves," rather than high in the canopy, and it has been collected from *Miconia* shrubs. Microbes that live inside the insect, called endosymbionts, have been recorded in it too. ## An Electric Sense, Tested on a Cousin A 2025 study found that another treehopper, *Poppea capricornis*, "can detect electric fields, responding behaviorally," and that the wasps that hunt treehoppers and the stingless bees that guard them in exchange for honeydew carry measurably different charges, so a treehopper may be able to "distinguish friend from foe via electroreception alone." *Bocydium globulare* was not among the living insects tested. It appears in that paper as a dried museum specimen under an electron microscope, carrying pit-shaped sensory hairs on its wing like the ones the researchers argue may work as electroreceptors. Their computer model of an extreme pronotum, not of this animal, puts the electric field in the first 0.1 mm around it at "over 100 kV/m, compared to approximately 3 kV/m around the nonextreme pronotum." ## Frequently Asked Questions ### What is the crown on its back actually for? No one has shown what it does. One idea, published in 1903, is that the globes mimic Neotropical seeds or small, spiny fruit. The entomologists who reviewed the genus in 1999 wrote that the actual function of the peculiar pronotal structures is unknown, as are the life histories of many of the species. *(Source: [Cryan & Deitz 1999]())* ### How big is a Brazilian treehopper? The 1999 revision of its genus does not measure this species on its own. The genus, Bocydium, holds 15 species, and that review diagnoses the whole genus at a total length of 4.6 to 7.5 millimeters, roughly the size of a match head. *(Source: [Cryan & Deitz 1999]())* ### Can it really sense electric fields through its crown? It has not been tested in this species. A 2025 study showed that a relative, Poppea capricornis, can detect electric fields and responds to them behaviorally. Bocydium globulare was not among the living insects tested: it appears in that study as a dried museum specimen, imaged under an electron microscope to show the pit-shaped sensory hairs on its wing that the researchers think may work as electroreceptors. *(Source: [England et al. 2025]())* ## Sources 1. [Cryan & Deitz (1999). Review of the New World treehopper tribe Stegaspidini (Hemiptera: Membracidae: Stegaspidinae): I. Bocydium Latreille, Lirania Stal, and Smerdalea Fowler. Proceedings of the Entomological Society of Washington 101(3): 469-489.]() 2. [England et al. (2025). Electroreception in treehoppers: How extreme morphologies can increase electrical sensitivity. Proceedings of the National Academy of Sciences.]() 3. [Adachi et al. (2020). Structure and development of the complex helmet of treehoppers (Insecta: Hemiptera: Membracidae). Zoological Letters.]() *Published September 6, 2026. 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