Aphids are small sap-sucking insects and members of the superfamily Aphidoidea. Common names include greenfly and blackfly, although individuals within a species can vary widely in color. The group includes the fluffy white woolly aphids. A typical life cycle involves flightless females giving live birth to female nymphs—who may also be already pregnant, an adaptation scientists call telescoping generations—without the involvement of males. Maturing rapidly, females breed profusely so that the number of these insects multiplies quickly. Winged females may develop later in the season, allowing the insects to colonize new plants. In temperate regions, a phase of sexual reproduction occurs in the autumn, with the insects often overwintering as eggs.
Hemiptera is an order of insects, commonly called true bugs, comprising over 80,000 species within groups such as the cicadas, aphids, planthoppers, leafhoppers, assassin bugs, bed bugs, and shield bugs. They range in size from 1 mm (0.04 in) to around 15 cm (6 in), and share a common arrangement of piercing-sucking mouthparts. The name "true bugs" is often limited to the suborder Heteroptera.
The Heteroptera are a group of about 40,000 species of insects in the order Hemiptera. They are sometimes called "true bugs", though that name more commonly refers to the Hemiptera as a whole. "Typical bugs" might be used as a more unequivocal alternative, since the heteropterans are most consistently and universally termed "bugs" among the Hemiptera. "Heteroptera" is Greek for "different wings": most species have forewings with both membranous and hardened portions ; members of the primitive sub-group Enicocephalomorpha have completely membranous wings.
Homoptera is a suborder of order Hemiptera that is considered by some taxonomists to be paraphyletic, and therefore deprecated (obsolete). It was therefore split into the suborders Sternorrhyncha, Auchenorrhyncha, and Coleorrhyncha. The earlier work was based on nuclear DNA, but more recent phylogenetic analysis using mitochondrial DNA suggest that Homoptera may be a monophyletic group after all, a sister group of Heteroptera. The cause of the disparity in the analyses is suggested to be the long branch attraction effect in phylogenetic analysis, due to rapidly evolving DNA regions.
Whiteflies are Hemipterans that typically feed on the undersides of plant leaves. They comprise the family Aleyrodidae, the only family in the superfamily Aleyrodoidea. More than 1550 species have been described.
Psyllidae, the jumping plant lice or psyllids, are a family of small plant-feeding insects that tend to be very host-specific, i.e. each plant-louse species only feeds on one plant species (monophagous) or feeds on a few closely related plants (oligophagous). Together with aphids, phylloxerans, scale insects and whiteflies, they form the group called Sternorrhyncha, which is considered to be the most "primitive" group within the true bugs (Hemiptera). They have traditionally been considered a single family, Psyllidae, but recent classifications divide the group into a total of seven families; the present restricted definition still includes more than 70 genera in the Psyllidae. Psyllid fossils have been found from the Early Permian before the flowering plants evolved. The explosive diversification of the flowering plants in the Cretaceous was paralleled by a massive diversification of associated insects, and many of the morphological and metabolic characters that the flowering plants exhibit may have evolved as defenses against herbivorous insects.
Scale insects are small insects of the order Hemiptera, suborder Sternorrhyncha. Of dramatically variable appearance and extreme sexual dimorphism, they comprise the infraorder Coccomorpha which is considered a more convenient grouping than the superfamily Coccoidea due to taxonomic uncertainties. Adult females typically have soft bodies and no limbs, and are concealed underneath domed scales, extruding quantities of wax for protection. Some species are hermaphroditic, with a combined ovotestis instead of separate ovaries and testes. Males, in the species where they occur, have legs and sometimes wings, and resemble small flies. Scale insects are herbivores, piercing plant tissues with their mouthparts and remaining in one place, feeding on sap. The excess fluid they imbibe is secreted as honeydew on which sooty mold tends to grow. The insects often have a mutualistic relationship with ants, which feed on the honeydew and protect them from predators. There are about 8,000 described species.
Leafhopper is the common name for any species from the family Cicadellidae. These minute insects, colloquially known as hoppers, are plant feeders that suck plant sap from grass, shrubs, or trees. Their hind legs are modified for jumping, and are covered with hairs that facilitate the spreading of a secretion over their bodies that acts as a water repellent and carrier of pheromones. They undergo a partial metamorphosis, and have various host associations, varying from very generalized to very specific. Some species have a cosmopolitan distribution, or occur throughout the temperate and tropical regions. Some are pests or vectors of plant viruses and phytoplasmas. The family is distributed all over the world, and constitutes the second-largest hemipteran family, with at least 20,000 described species.
The Peloridiidae or moss bugs are a family of true bugs, comprising eighteen genera and thirty-four species. They are small, ranging in length from 2 to 4 mm, rarely seen, peculiarly lumpy, flattened bugs found in Patagonia, New Zealand, eastern Australia, Lord Howe Island, and New Caledonia. Peloridiids are found amongst mosses and liverworts, commonly in association with southern beech forests. They have become known as moss bugs for their habit of feeding on mosses. Almost all Peloridiidae species are flightless, except one. Their present distribution suggests they have existed since before the breakup of Gondwana. They are the only living members of the suborder Coleorrhyncha, which first appeared in the Upper Permian, over 250 million years ago.
The Auchenorrhyncha suborder of the Hemiptera contains most of the familiar members of what was called the "Homoptera" – groups such as cicadas, leafhoppers, treehoppers, planthoppers, and spittlebugs. The aphids and scale insects are the other well-known "Homoptera", and they are in the suborder Sternorrhyncha.
Cicadomorpha is an infraorder of the insect order Hemiptera which contains the cicadas, leafhoppers, treehoppers, and spittlebugs. There are approximately 35,000 described species worldwide. Distributed worldwide, all members of this group are plant-feeders, and many produce either audible sounds or substrate vibrations as a form of communication. The earliest fossils of cicadomorphs first appear during the Late Permian.
The superfamily Membracoidea of sap-sucking true-bugs includes two of the largest families within what used to be called the "Homoptera": the leafhoppers (Cicadellidae) and the treehoppers (Membracidae). The other families in this group are quite small, and have, at various points, generally been included as members within other families, though they are all presently considered to be valid, monophyletic groups. The relict family Myerslopiidae is restricted to New Zealand and South America while the Melizoderidae consist of two genera restricted to South America. The great diversity of Neotropical taxa suggests that the group originated in that region.
Coccinellidae is a widespread family of small beetles. They are commonly known as ladybugs in North America and ladybirds in the United Kingdom; "lady" refers to mother Mary. Entomologists use the names ladybird beetles or lady beetles to avoid confusion with true bugs. The more than 6,000 described species have a global distribution and are found in a variety of habitats. They are oval beetles with a domed back and flat underside. Many of the species have conspicuous aposematic (warning) colours and patterns, such as red with black spots, that warn potential predators that they taste bad.
Lethocerus is a genus of the hemipteran family Belostomatidae, known colloquially as giant water bugs, toe biters and electric light bugs, distributed in tropical, subtropical and temperate areas of the world. The greatest diversity of species occurs in the Americas, with only a single species in Europe, two in Africa, two in Australia and three in Asia. It includes the largest true bugs with species capable of reaching a length of over 12 centimetres (4.7 in). The South American L. grandis and L. maximus are the only species to commonly exceed 9 cm (3.5 in), with more typical lengths for the remaining species being between 4.5 and 9 cm. Lethocerus sp. are distinguished from other genera in the Lethocerinae by two symmetrical furrows in the inner pad of setae on the fore femur, the external borders of parasternites II and III narrowed and nearly straight, and with the setae of the tarsomeres following the line of the tibial setae.
Paraneoptera or Acercaria is a superorder of insects which includes lice, thrips, and hemipterans, the true bugs. It also includes the extinct order Permopsocida, known from fossils dating from the Early Permian to the mid-Cretaceous.
Coleorrhyncha or Peloridiomorpha, also known as moss bugs or beetle bugs, are a suborder of Hemiptera and represent an ancient lineage of moss-feeding insects. They show some similarities to the Heteroptera but have been considered distinct. It has a single extant family, the Peloridiidae. They are 2 to 5 millimetres in length, and feed on moss and liverworts. They have wings in some species which are reduced in others but all species are flightless and live in damp moss habitats and are associated with the distribution of Nothofagus trees in Australia, New Zealand, New Caledonia, and South America, which all were formerly part of the supercontinent Gondwana.
Phylloxeridae is a small family of plant-parasitic hemipterans closely related to aphids with only 75 described species. This group comprises two subfamilies and 11 genera with one that is fossil. The genus type is Phylloxera. The Phylloxeridae species are usually called phylloxerans or phylloxerids.
Aphidomorpha is an infraorder within the insect order Sternorrhyncha which includes the aphids and their allies in the superfamilies Adelgoidea, Phylloxeroidea and Aphidoidea. This group also includes numerous fossil taxa of uncertain placement, such as these other superfamilies Triassoaphidoidea , Genaphidoidea, Palaeoaphidoidea, and Tajmyraphidoidea.
Dinglidae is an extinct family of hemipteran insects belonging to the suborder Sternorrhyncha. It does not belong to any of the major living sternorrhynchan subgroups, and is a distinct lineage most closely related to whiteflies. The family contains two genera, both of which are known from the mid-Cretaceous Burmese amber of Myanmar.
Trypetimorpha is a genus of bugs in the family Tropiduchidae; species are recorded from mainland Europe, Africa, Asia and Australia.
