Heteroptera

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Heteroptera
Wasserlaufer bei der Paarung crop.jpg
Two water striders mating
Scientific classification Red Pencil Icon.png
Kingdom: Animalia
Phylum: Arthropoda
Class: Insecta
Order: Hemiptera
Suborder: Heteroptera
Latreille, 1810
Infraorders

The Heteroptera are a group of about 40,000 species of insects in the order Hemiptera. They are sometimes called "true bugs", [1] 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 (called hemelytra); members of the primitive sub-group Enicocephalomorpha have completely membranous wings.

Contents

The name "Heteroptera" is used in two very different ways in modern classifications. In Linnean nomenclature, it commonly appears as a suborder within the order Hemiptera, where it can be paraphyletic or monophyletic depending on its delimitation. In phylogenetic nomenclature, it is used as an unranked clade within the Prosorrhyncha clade, which in turn is in the Hemiptera clade. This results from the realization that the Coleorrhyncha are just "living fossil" relatives of the traditional Heteroptera, close enough to them to be united with that group.

The Gerromorpha and Nepomorpha contain most of the aquatic and semiaquatic members of the Heteroptera, while nearly all of the remaining groups that are common and familiar are in the Cimicomorpha and Pentatomomorpha.

Classification

The use of the name "Heteroptera" has had the rank of order, dating back to 1810 by Pierre André Latreille. Only recently has it been relegated to a subsidiary rank within a larger definition of Hemiptera, so many reference works still include it as an order. Whether to continue treating it as a suborder is still a subject of some controversy, as is whether the name itself should ever be used, although three basic approaches ranging from abolishing it entirely to maintaining the taxonomy with a slight change in systematics is proposed, two of which (but not the traditional one) agree with the phylogeny. The competing classifications call for a preference for two suborders versus one when the "living fossil" family Peloridiidae is taken into consideration:

In one revised classification proposed in 1995, [2] the name of the suborder is Prosorrhyncha, and Heteroptera is a rankless subgroup within it. The only difference between Heteroptera and Prosorrhyncha is that the latter includes the family Peloridiidae, which is a tiny relictual group that is in its own monotypic superfamily and infraorder. In other words, the Heteroptera and Prosorrhyncha sensu Sorensen et al. are identical except that Prosorrhyncha contains one additional infraorder, called Peloridiomorpha (comprising only 13 small genera). The ongoing conflict between traditional, Linnaean classifications and nontraditional classifications is exemplified by the problem inherent in continued usage of the name Heteroptera when it no longer can be matched to any standard Linnaean rank (as it falls below suborder but above infraorder). If this classification succeeds, then the "Heteroptera" grouping may be discarded, but in that case it is likely that no ranks will be used at all according to the standards of phylogenetic nomenclature.

In the traditional classification, [3] the Peloridiidae are retained as their own suborder, called Coleorrhyncha; "Heteroptera" is treated the same. Functionally, the only difference between this classification and the preceding is that the former uses the name Prosorrhyncha to refer to a particular clade, while the traditional approach divides this into the paraphyletic Heteroptera and the monophyletic Coleorrhyncha. Many believe it is preferable to use only one name because the characteristics of the two traditional suborders are too closely related to be treated as separate.

Alternatively, [4] the modified approach of placing Coleorrhyncha 'within' the Heteroptera can be used. Indeed, as that solution preserves the well-known Heteroptera at the taxonomic rank they traditionally hold while making them a good monophyletic group, it seems preferable to the paraphyletic "Heteroptera" used in older works. In that case, the "core" Heteroptera could be considered a section – as yet unnamed, mainly because the Prosorrhyncha were proposed earlier – within the "expanded" Heteroptera, or the latter could simply be described as consisting of a basal "living fossil" lineage and a more apomorphic main radiation. Whether the name "Coleorrhyncha" is to be retained for the basal lineage or whether the more consistent "Peloridiomorpha" is used instead is a matter of taste, as described below.

Separate from the question of the actual "closeness" of Heteroptera and Coleorrhyncha is the potential disruption to traditional construction of names; there seems to be reluctance among hemipterists to abandon the use of "Heteroptera". This can be seen by the name itself, as it is a violation of convention to use the ending "-ptera" for any rank above genus other than an order – though since it is a convention rather than a mandatory rule of Linnean nomenclature, taxonomists are technically free to violate it (which is why, for example, not all insect orders end in "-ptera", e.g., Odonata). However, in most cases when such conventions are violated, it does not create an internal conflict as in the present case (that is, the order Hemiptera has a suborder named Heteroptera, which is an internal conflict). At least some hemipterists argue that the name Heteroptera should be dropped entirely to eliminate this internal conflict, though the third possibility offers a workaround. In that case, to achieve full consistency of names "Coleorrhyncha" would probably be dropped in favor of "Peloridiomorpha".

An assassin bug nymph Zelus bug nymph.jpg
An assassin bug nymph

Selected families of Heteroptera

Heteropteran anatomy

Generalized morphology of a shield bug Pentatomoidea Heteroptera morphology-d.svg
Generalized morphology of a shield bug Pentatomoidea

A: head; B: thorax; C: abdomen. 1: claws; 2: tarsus; 3: tibia; 4: femur; 8: compound eye; 9: antenna; 10: clypeus; 23: laterotergites; 25: pronotum; 26: scutellum; 27: clavus; 28: corium; 29: embolium; 30: membrane.

"Waterbug"

"Waterbug" is a common name for a number of aquatic insects, most of which are classified in the infraorders Gerromorpha and Nepomorpha of the order Hemiptera. The latter infraorder contains those taxa that were once known as the "Cryptocerata". Note that the term "water bug" is very often applied to some cockroaches, which are not true bugs and as Dictyoptera not even close to them (true bugs are Paraneoptera).

Selected families of water bugs

See also

Related Research Articles

Hemiptera Order of insects often called bugs

The Hemiptera or true bugs are an order of insects comprising some 50,000 to 80,000 species of groups such as the cicadas, aphids, planthoppers, leafhoppers, 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 sucking mouthparts. The name "true bugs" is often limited to the suborder Heteroptera. Many insects commonly known as "bugs", especially in American English, belong to other orders; for example, the lovebug is a fly and the May bug and ladybug are beetles.

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.

Plecoptera order of insects

The Plecoptera are an order of insects, commonly known as stoneflies. Some 3,500 species are described worldwide, with new species still being discovered. Stoneflies are found worldwide, except Antarctica. Stoneflies are believed to be one of the most primitive groups of Neoptera, with close relatives identified from the Carboniferous and Lower Permian geological periods, while true stoneflies are known from fossils only a bit younger. Their modern diversity, however, apparently is of Mesozoic origin.

Leafhopper Family of insects

A 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.

Gerromorpha infraorder of insects

The Gerromorpha comprise an infraorder of insects in the "true bug" order Hemiptera. These "typical" bugs are commonly called semiaquatic bugs or shore-inhabiting bugs. The Ochteroidea are also found in shore habitat, while the Gerromorpha are actually most often encountered running around on the water surface, being kept from sinking by surface tension and their water-repellent legs. Well-known members of the Gerromorpha are the namesake Gerridae.

Nepomorpha infraorder of insects

Nepomorpha is an infraorder of insects in the "true bug" order (Hemiptera). They belong to the "typical" bugs of the suborder Heteroptera. Due to their aquatic habits, these animals are known as true water bugs. They occur all over the world outside the polar regions, with about 2,000 species altogether. The Nepomorpha can be distinguished from related Heteroptera by their missing or vestigial ocelli. Also, as referred to by the obsolete name Cryptocerata, their antennae are reduced, with weak muscles, and usually carried tucked against the head.

Pentatomomorpha infraorder of insects

The Pentatomomorpha comprise an infraorder of insects in the true bug order Hemiptera. It unites such animals as the stink bugs (Pentatomidae), flat bugs (Aradidae), seed bugs, etc. They are closely related to the Cimicomorpha.

Peloridiidae family of insects

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. All the Peloridiidae species are flightless, except one. Their present distribution suggests they have existed since before the breakup of Gondwana, and their relation to Heteroptera dates back to at least the upper Permian, more than 230 million years ago. 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.

Auchenorrhyncha suborder of insects

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. Lesser-known insects largely regarded as Homoptera are the Coleorrhyncha. However, the taxonomic status of the Hemiptera and Homoptera is currently under investigation and discussion. See Heteroptera and Prosorrhyncha for more information.

The name Prosorrhyncha is a name for a suborder of Hemiptera, comprising a grouping of the traditional taxon "Heteroptera" plus its sister taxon, the family Peloridiidae. There is no agreement on the status of this taxon, as there are two competing classifications regarding this branch of the Hemiptera; while some hemipterists follow this classification, it has by no means been accepted universally. See the Heteroptera article for the detailed discussion, and a comparison of the two taxoboxes.

Phylogenetic nomenclature, often called cladistic nomenclature, is a method of nomenclature for taxa in biology that uses phylogenetic definitions for taxon names as explained below. This contrasts with the traditional approach, in which taxon names are defined by a type, which can be a specimen or a taxon of lower rank, and a description in words. Phylogenetic nomenclature is currently not regulated, but the International Code of Phylogenetic Nomenclature (PhyloCode) is intended to regulate it once it is ratified.

Taxonomic rank Level in a taxonomic hierarchy

In biological classification, taxonomic rank is the relative level of a group of organisms in a taxonomic hierarchy. Examples of taxonomic ranks are species, genus, family, order, class, phylum, kingdom, domain, etc.

Pleidae family of insects

Pleidae, the pygmy backswimmers, is a family of aquatic insects in the order Hemiptera. There are 37 species in three genera, distributed across most of the world, except the polar regions and remote oceanic islands.

Coleorrhyncha suborder of insects

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 that evolved in the southern paleo-continent Gondwana. They show some similarities to the Heteroptera but have been considered distinct. It has a single extant family, the Peloridiidae. Three other families have been established on the basis of fossils and these include the more ancient Progonocimicidae and the later Karabasiidae and Hoploridiidae. The Coleorrhyncha were earlier included within the "Homoptera" but based on studies of their morphological similarities as well as molecular phylogeny are now considered as a sister group of the Heteroptera. 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.

Yuri Alexandrovich Popov Russian paleoentomologist

Yuri Alexandrovich Popov was a Russian paleoentomologist, an authority on the taxonomy and evolution of fossil true bugs (Heteroptera) and Coleorrhyncha. He described more than 20 new families and subfamilies and 300 new genera and species from the Mesozoic and Cenozoic. He also was one of the founders of the modern higher classification of true bugs: three of seven heteropteran infraorders have been established by him. He was the author of more than 170 publications, including a classic monograph on the evolution of water bugs.

Gerroidea superfamily of insects

Gerroidea is a superfamily of semiaquatic bugs in the order Hemiptera. There are at least 3 families and more than 2,000 described species in Gerroidea.

<i>Hebrus</i> (bug) genus of insects

Hebrus is a genus of velvet water bugs in the family Hebridae. There are at least 160 described species in Hebrus.

Mesoveliidae family of insects

Mesoveliidae is a family of water treaders in the order Hemiptera. There are about 16 genera and at least 50 described species in Mesoveliidae.

Micronectinae

Micronectinae is a subfamily of water boatmen in the family Corixidae. There are at least two genera and two described species in Micronectinae.

<i>Microvelia buenoi</i> species of insect

Microvelia buenoi is a species of smaller water strider in the family Veliidae. It is found in Europe & Northern Asia and North America.

References

  1. Tree of Life Web Project (2005): Heteroptera. True bugs. Version of January 1, 2005. Retrieved July 28, 2008.
  2. Sorensen, J. T., B. C. Campbell, R. J. Gill & J. D. Steffen-Campbell (1995): Non-monophyly of Auchenorrhyncha ("Homoptera"), based upon 18S rDNA phylogeny: eco-evolutionary and cladistic implications with pre-Heteropteroidea Hemiptera (s.l.) and a proposal for new monophyletic suborders. Pan-Pacific Entomologist71 (1): 31–60.
  3. Maddison, David R. (1995): Tree of Life Web ProjectHemiptera. True bugs, cicadas, leafhoppers, aphids, etc.. Version of January 1, 2005. Retrieved July 28, 2008.
  4. Cassis, Gerasimos & Gross, Gordon (1995): Australian Biological Resources Study – Hemiptera: Heteroptera (Coleorrhyncha to Cimicomorpha). Gerrids, Reduviids, Water-striders. Version of June 30, 1995. Retrieved July 28, 2008.

Further reading