Fall is the time when many kinds of true bugs, in the order Hemiptera, reach peak abundance, before going into hiding for the winter. This includes stink bugs, leaf-footed bugs, plant bugs, aphids, whiteflies, psyllids, and leafhoppers. If you haven’t looked closely at leafhoppers, there is a great deal you are missing.
Leafhoppers use piercing-sucking mouthparts to feed on plant sap. It isn’t a nutritious diet, so they imbibe great quantities, and excrete a copious amount of sugary, sticky, liquid waste. Some leafhoppers are known as sharpshooters, in part because they eject their waste like a squirt gun fires water. This action keeps their waste from gumming up their own bodies, and also works to not draw the attention of potential predators and parasitoids that could track them by their excrement.
There are at least 3,000 members of the family Cicadellidae found north of Mexico, and over 22,000 globally. More are likely to be separated from existing species by molecular DNA analysis. Leafhoppers range in size from two to thirty millimeters in length. Most of the diversity occurs in the range under five millimeters.
These are streamlined insects, usually with a narrow body form. The hind legs are long, built for jumping, and there are two rows of many spines on those hind legs. Spittlebugs and planthoppers do not have those rows of spines. The antennae are relatively sort, consisting of hair-like filaments. In most views, without magnification, they appear to have no antennae at all.
Break out your magnifiers, you are gonna wanna see this. Leafhoppers can be shockingly beautiful, with striking patterns of ivory and red, or blue and red, in stripes or bands, or spotted. At this time of year, species that are normally green may take on the hues of autumn foliage, the better to camouflage themselves. There is almost no end to the “fashion spectrum” for leafhoppers.
You cannot rely on color patterns alone to differentiate species. Newly-minted adults will be paler, even lacking markings initially until pigments manifest and the exoskeleton hardens after that final molt. There may be some sexual dimorphism expressed as differences in color between males and females. There is no doubt individual variation, too.
Right now, where we are in northeast Kansas, you cannot avoid leafhoppers. They are in the air, in your lawn, on foliage (especially the underside of leaves), and landing briefly on buildings, fences, or you. Turn on your porch light at night, and you will see a diversity of them flying in.
Try taking photos with a camera or phone that has good macro capabilities. The images show here were taken by me with a Canon PowerShot SX70 camera, one of the bridge cameras or “superzooms” that allow the casual photographer to take a variety of images without changing lenses. Approach the insect slowly. Many will leap, or take flight, but eventually you will have a cooperative specimen.
Whether leafhoppers are pests depends on who you ask, and maybe when you ask. Some leafhoppers, if they alight on you, will probe with their mouthparts, and it is surprisingly painful, albeit briefly, and in an annoying, not agonizing, way. In natural ecosystems, native leafhoppers are part of the food web. In agricultural systems, they can be problematic.
Some species are vectors of plant viruses that can wreak havoc on crops. Others transmit bacterial diseases. The mechanical and chemical aspects of their normal feeding of course results in some damage to the plant. On leaves, heavy feeding can result in white or yellow stippling where their mouthparts have entered, and chlorophyl has been extracted.
Females insert their eggs into living plant tissue, which also causes damage. Leafhoppers have a general life cycle that includes about five immature instars, an instar being the interval between molts. The young are called nymphs, and they gradually get larger over time. The final molt results in the adult insect. Adults of most species have wings and fly well.
By sharing your photos on platforms like iNaturalist and Buggide.net, you can help scientists learn more about the distribution, host plants, seasonal presence, and other attributes of leafhoppers. You may add new county records, or state or provincial records, or even detect a recently-arrived leafhopper of foreign origin. In any event, enjoy the remarkable beauty of these tiny creatures.
Check out my observations on iNat, and my Flickr album for inspiration.
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