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"Planthoppers are small jumping insects that often have unusually angled or pointed head shapes. Their antennae are attached to their faces below the eyes, on the sides of the head. The two basal segments of each antenna are thick and rather bulbous, while the outer segment is a very thin bristle. Some wings are large enough to make them resemble tiny moths, caddisflies, or grasshoppers, while the wings of others are barely long enough to cover the first few segments of the abdomen."
"Planthoppers belong to the Family Flatidae (Order Hemiptera; Suborder Auchenorrhyncha), and are sometimes referred to as "flatids." Planthopper adults are 1/4- 3/8" long, purplish blue, lime green, or powdery white, and they hold their broad wings vertically in a tent-like fashion covering the sides of the body and legs."
"Like other true bugs, planthoppers begin life as an egg and then, growing, undergo a number of immature stages (nymphs) before a final molt renders them a winged, sexually mature adult."
They are recognizable by "a whitish layer that protects against adverse abiotic and biotic factors, such as entomopathogenic fungi, parasitoid insects, and predators."
"Secretion of wax by adult fulgoroids is not as common as it is in immatures, but it is known for a number of species... " "In the Nearctic flatid Metcalfa pruinosa (Say), most wax is secreted on the forewings of both sexes and on the anal tube of females... Although the function of the anal tube wax is unknown, the wax layer that covers the body and forewings may play an important role in protection against abiotic factors and prevent smearing the cuticle with honeydew."
"Malcolm Burrows and Gregory Sutton, a pair of biologists from the University of Cambridge in the U.K., discovered that juveniles of the species have an intricate gearing system that locks their back legs together, allowing both appendages to rotate at the exact same instant, causing the tiny creatures jump forward...The finely toothed gears in their legs allow this to happen. “In Issus, the skeleton is used to solve a complex problem that the brain and nervous system can’t,” Burrows said...as the juveniles grow up and their skin molts away, they fail to regrow these gear teeth, and the adult legs are synchronized by an alternate mechanism (a series of protrusions extend from both hind legs, and push the other leg into action). Burrows and Sutton hypothesize that this could be explained by the fragility of the gearing: if one tooth breaks, it limits the effectiveness of the design. This isn’t such a big problem for the juveniles, who repeatedly molt and grow new gears before adulthood..."
"Vibrations through substrates are an important source of information for diverse organisms, from nematodes to elephants. The fundamental challenge for small animals using vibrational communication is to move their limited mass fast enough to provide sufficient kinetic energy for effective information transfer through the substrate whilst optimising energy efficiency over repeated cycles. Here, we describe a vibratory organ found across a commercially important group of plant-feeding insects, the planthoppers (Hemiptera: Fulgoromorpha). This elastic recoil snapping organ generates substrate-borne broadband vibrations using fast, cyclical abdominal motion that transfers kinetic energy to the substrate through the legs. Elastic potential energy is stored and released twice using two different latched energy-storage mechanisms, each utilising a different form of elastic recoil to increase the speed of motion."
Video: Oxford researchers discover how planthoppers communicate
"Preharvest losses caused by pests can threaten rice production, food security, and rural livelihoods. This is especially so when massive pest outbreaks occur at later crop stages. Affected farmers suffer heavy financial losses, fall into debt, and even commit suicide (OAE2010). Such pest outbreaks can have devastating effects on rice production as rice ecosystems continue to remain vulnerable. A large variety of chemicals collectively known as pesticides are used by rice farmers in Asia to control pests. Insecticides are used to control insects, fungicides to control diseases, herbicides to control weeds, and molluscicides to control snails.In many countries, farmers often respond to insect pest threats by increasing insecticide use as prophylactic applications to protect their crops. Oftentimes, the sprays do not work as most farmers tend to overestimate the pest damages and losses, and thus apply more pesticides than necessary. Paradoxically, excessive use of insecticides does not help control pest outbreaks but seems to even induce their numbers. Further, farmers increasingly rely on insecticides that are toxic and have adverse health implications....Planthoppers are typically r-strategists that live and breed only in rice and are completely adapted to the rice ecosystem. They normally exist in rice fields in very low numbers of less than five planthoppers per plant and do not damage the rice plants or cause yield loss (Heong, Aquino, and Barrion 1992). However, they can destroy crops in 2 weeks if their populations increase exponentially."
"The brown planthopper (BPH), Nilaparvata lugens (Stål; Hemiptera: Delphacidae) is a piercing-sucking pest that causes serious damage to rice plants by sucking the phloem sap from the plants and transmitting viruses. During courtship, the BPH vibrates its abdomen to produce signals that are transmitted to rice plants through its legs. Male BPHs search, locate, and mate with female BPHs after they exchange courtship signals with each other. Currently, spraying chemical pesticides is still the primary method for controlling BPH populations in paddy fields, although this approach has led to severe environmental pollution. A physical control method based on BPH courtship disruption to reduce the mating rate is a promising strategy for cutting environmental pollution. To acquire effective courtship disruptive signals, we developed a vibration signal recording, monitoring, and playback system for BPHs. Using this system, ... the courtship behavior of BPHs can be disrupted by using specific artificial disruptive signals."
Pretty planthoppers:
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