Pterygota ( ) is a subclass of

insect Insects (from Latin ') are Hexapoda, hexapod invertebrates of the class (biology), class Insecta. They are the largest group within the arthropod phylum. Insects have a chitinous exoskeleton, a three-part body (Insect morphology#Head, head, ...

s that includes all winged insects and groups who lost them secondarily. Pterygota group comprises 99.9% of all insects. The orders not included are the

Archaeognatha The Archaeognatha are an order of apterygotes, known by various common names such as jumping bristletails. Among extant insect taxa they are some of the most evolutionarily primitive; they appeared in the Middle Devonian period at about the sa ...

(jumping bristletails) and the

Zygentoma Zygentoma are an order in the class Insecta, and consist of about 550 known species. The Zygentoma include the so-called silverfish or fishmoths, and the firebrats. A conspicuous feature of the order are the three long caudal filaments. The t ...

(

silverfish The silverfish (''Lepisma saccharinum'') is a species of small, primitive, wingless insect in the order Zygentoma (formerly Thysanura). Its common name derives from the insect's silvery light grey colour, combined with the fish-like appearanc ...

es and

firebrat The firebrat (''Thermobia domestica'') is a small insect (typically 1–1.5 cm) in the order Zygentoma. Habitat Firebrats prefer relatively warm temperatures (36–39 °C) and require some humidity. They are commonly found ...

s), two primitively wingless insect orders. Unlike Archaeognatha and Zygentoma, the pterygotes do not have styli or vesicles on their abdomen (also absent in some zygentomans), and with the exception of the majority of mayflies, are also missing the median terminal filament which is present in the ancestrally wingless insects. The oldest known representatives of the group appeared during the mid-Carboniferous, around 328–324 million years ago, and the group subsequently underwent rapid diversification. Claims that they originated substantially earlier during the

Silurian The Silurian ( ) is a geologic period and system spanning 23.5 million years from the end of the Ordovician Period, at million years ago ( Mya), to the beginning of the Devonian Period, Mya. The Silurian is the third and shortest period of t ...

Devonian The Devonian ( ) is a period (geology), geologic period and system (stratigraphy), system of the Paleozoic era (geology), era during the Phanerozoic eon (geology), eon, spanning 60.3 million years from the end of the preceding Silurian per ...

based on

molecular clock The molecular clock is a figurative term for a technique that uses the mutation rate of biomolecules to deduce the time in prehistory when two or more life forms diverged. The biomolecular data used for such calculations are usually nucleot ...

estimates are unlikely based on the fossil record, and are likely analytical artefacts. __TOC__

Systematics

Traditionally, this group was divided into the

infraclass In biology, taxonomic rank (which some authors prefer to call nomenclatural rank because ranking is part of nomenclature rather than taxonomy proper, according to some definitions of these terms) is the relative or absolute level of a group of or ...

Paleoptera The name Palaeoptera (from Greek ( 'old') + ( 'wing')) has been traditionally applied to those ancestral groups of winged insects (most of them extinct) that lacked the ability to fold the wings back over the abdomen as characterizes the Neop ...

and

Neoptera Neoptera (Ancient Greek ''néos'' ("new") + ''pterón'' ("wing")) is a classification group that includes most orders of the winged insects, specifically those that can flex their wings over their abdomens. This is in contrast with the more basa ...

. The former are nowadays strongly suspected of being

paraphyletic Paraphyly is a taxonomic term describing a grouping that consists of the grouping's last common ancestor and some but not all of its descendant lineages. The grouping is said to be paraphyletic ''with respect to'' the excluded subgroups. In co ...

, and better treatments (such as dividing or dissolving the group) are presently being discussed. In addition, it is not clear how exactly the neopterans are related among each other. The

Exopterygota The Exopterygota (Ancient Greek ''ἔξω'' (éxō, "outside") + ''πτερόν'' (pterón, "wing") + Neo-Latin ''-ota'' ("having")), also known as Hemimetabola, are a superorder of insects of the subclass Pterygota in the infraclass Neoptera, ...

might be a similar assemblage of rather ancient

hemimetabolous Hemimetabolism or hemimetaboly, also called partial metamorphosis and paurometabolism,McGavin, George C. ''Essential Entomology: An Order-by-Order Introduction''. Oxford: Oxford University Press, 2001. pp. 20. is the mode of development of certain ...

insects among the Neoptera like the Palaeoptera are among insects as a whole. The

holometabolous Holometabolism, also called complete metamorphosis, is a form of insect development which includes four life stages: egg, larva, pupa, and imago (or adult). Holometabolism is a synapomorphic trait of all insects in the clade Holometabola. Immatur ...

Endopterygota Holometabola (from Ancient Greek "complete" + "change"), also known as Endopterygota (from "inner" + "wing" + Neo-Latin "-having"), is a supra- ordinal clade of insects within the infraclass Neoptera that go through distinctive larval, pupal ...

seem to be very close relatives, indeed, but nonetheless appear to contain several

clades In biology, a clade (), also known as a monophyletic group or natural group, is a group of organisms that is composed of a common ancestor and all of its descendants. Clades are the fundamental unit of cladistics, a modern approach to taxonomy ...

of related orders, the status of which is not agreed upon. The following scheme uses finer divisions than the one above, which is not well-suited to correctly accommodating the fossil groups.

Classification

* Order Ephemeroptera (mayflies) * Superorder

Palaeodictyopteroidea The Palaeodictyopteroidea or Paleodictyopterida are an extinct superorder of Palaeozoic beaked insects, characterised by unique mouthparts consisting of 5 stylets. They represent the first important terrestrial herbivores, and the first major gro ...

** Order

Palaeodictyoptera The Palaeodictyoptera are an extinct order of medium-sized to very large, primitive Palaeozoic paleopterous insects. They are informative about the evolution of wings in insects. Overview They were characterized by beak-like mouthparts, used ...

†(extinct) ** Order

Megasecoptera Megasecoptera is a Paleozoic insect order. There are 22 known families of megasecopterans, with about 35 known genera. Overview Like all other paleodictyopteroids, the megasecopterans had sucking mouthparts. The suctorial mouth parts were proba ...

†(extinct) ** Order

Permothemistida Permothemistida is an extinct order of palaeozoic paleopterous insects. References Extinct insect orders Palaeodictyopteroidea {{paleo-insect-stub ...

†(extinct) ** Order

Diaphanopterodea The Diaphanopterodea or Paramegasecoptera are an extinct order of moderate to large-sized Palaeozoic insects. They are first known from the Middle Carboniferous (late Serpukhovian or early Bashkirian in age), and include some of the earliest know ...

†(extinct) *

Metapterygota Metapterygota is a clade of winged insects containing order Odonata and Infraclass Neoptera. They share morphological characteristics of a loss of caudal filaments and a subimago stage. Genetically the clade is supported by similarities in the mi ...

** Superorder Odonatoptera *** Order Protodonata or

Meganisoptera Meganisoptera is an extinct order of large dragonfly-like insects, informally known as griffenflies or (incorrectly) as giant dragonflies. The order was formerly named Protodonata, the "proto-Odonata", for their similar appearance and supposed r ...

†(extinct) *** Order

Protanisoptera The Odonatoptera are a superorder (sometimes treated as an order) of ancient winged insects, placed in the probably paraphyletic group Palaeoptera. The dragonflies and damselflies (which are placed in the subgroup Odonata) are the only liv ...

†(extinct) *** Order

Triadophlebioptera The Odonatoptera are a superorder (sometimes treated as an order) of ancient winged insects, placed in the probably paraphyletic group Palaeoptera. The dragonflies and damselflies (which are placed in the subgroup Odonata) are the only living mem ...

†(extinct) *** Order

Protozygoptera The Odonatoptera are a superorder (sometimes treated as an order) of ancient winged insects, placed in the probably paraphyletic group Palaeoptera. The dragonflies and damselflies (which are placed in the subgroup Odonata) are the only living m ...

or Archizygoptera †(extinct) *** Order

Odonata Odonata is an order of predatory flying insects that includes the dragonflies and damselflies (as well as the '' Epiophlebia'' damsel-dragonflies). The two major groups are distinguished with dragonflies (Anisoptera) usually being bulkier with ...

(

dragonflies A dragonfly is a flying insect belonging to the infraorder Anisoptera below the order Odonata. About 3,000 extant species of dragonflies are known. Most are tropical, with fewer species in temperate regions. Loss of wetland habitat threate ...

and

damselflies Damselflies are flying insects of the suborder Zygoptera in the order Odonata. They are similar to dragonflies (which constitute the other odonatan suborder, Epiprocta) but are usually smaller and have slimmer bodies. Most species fold the win ...

) ** Infraclass Neoptera ***

Polyneoptera The cohort Polyneoptera is one of the major groups of winged insects, comprising the Orthoptera (grasshoppers, crickets, etc.) and all other neopteran insects believed to be more closely related to Orthoptera than to any other insect orders. Th ...

**** Order

Caloneurodea Caloneurodea is an extinct order of polyneopteran neopteran insects in the superorder Orthopterida. Caloneurodea is known from fossils found in North America, Europe, Russia, and Asia and had a paleogeographic range confined to Laurussia. Famili ...

†(extinct) **** Order Glosselytrodea †(extinct) **** Order

Titanoptera Titanoptera is an extinct order of neopteran insects from late Carboniferous to Triassic periods. Titanopterans were very large in comparison with modern insects, some having wingspans of up to or even . Description Titanopterans are related ...

†(extinct) **** Order Protorthoptera †(extinct) **** Order

Plecoptera Plecoptera is an order (biology), 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 b ...

(stoneflies) **** Order

Embioptera The order Embioptera, commonly known as webspinners or footspinners, are a small group of mostly tropical and subtropical insects, classified under the subclass Pterygota. The order has also been called Embiodea or Embiidina. More than 400 spe ...

(webspinners) **** Order

Zoraptera The insect order (biology), order Zoraptera, commonly known as angel insects, contains small and soft bodied insects with two forms: winged with wings sheddable as in termites, dark and with eyes (compound) and ocelli (simple); or wingless, pale ...

(angel insects) **** Order

Dermaptera Earwigs make up the insect order Dermaptera. With about 2,000 species in 12 families, they are one of the smaller insect orders. Earwigs have characteristic cerci, a pair of forceps-like pincers on their abdomen, and membranous wings folde ...

(earwigs) **** Order

Orthoptera Orthoptera () is an order of insects that comprises the grasshoppers, locusts, and crickets, including closely related insects, such as the bush crickets or katydids and wētā. The order is subdivided into two suborders: Caelifera – gras ...

(

grasshopper Grasshoppers are a group of insects belonging to the suborder Caelifera. They are amongst what are possibly the most ancient living groups of chewing herbivorous insects, dating back to the early Triassic around 250 million years ago. Grassh ...

s, etc.) **** Order

Phasmatodea The Phasmatodea (also known as Phasmida or Phasmatoptera) are an Order (biology), order of insects whose members are variously known as stick insects, stick bugs, walkingsticks, stick animals, or bug sticks. They are also occasionally referred ...

(stick insects) **** Superorder

Notoptera Notoptera, also known as Xenonomia, is a clade of insects belonging to Polyneoptera. It contains two living groups, Mantophasmatidae (gladiators) native to southern Africa, and Grylloblattidae (ice crawlers) native to cold montane environment ...

***** Order

Grylloblattodea Grylloblattidae, commonly known as the icebugs or ice crawlers, is a family of extremophile (psychrophile) and wingless insects that live in the cold on top of mountains and the edges of glaciers. It is the only member of Grylloblattodea, which ...

(ice-crawlers) ***** Order

Mantophasmatodea Mantophasmatidae is a family of carnivorous wingless insects within the monotypic order Mantophasmatodea, which was discovered in Africa in 2001. Recent evidence indicates a sister group relationship with Grylloblattidae (classified in the orde ...

(gladiators) **** Superorder

Dictyoptera Dictyoptera (from Greek δίκτυον ''diktyon'' "net" and πτερόν ''pteron'' "wing") is an insect superorder that includes two extant orders of polyneopterous insects: the order Blattodea (termites and cockroaches together) and the or ...

***** Order

Blattodea Blattodea is an order (biology), order of insects that contains cockroaches and termites. Formerly, termites were considered a separate order, Isoptera, but genetics, genetic and molecular evidence suggests they evolved from within the cockroach ...

(cockroaches and termites) ***** Order

Mantodea Mantises are an Order (biology), order (Mantodea) of insects that contains List of mantis genera and species, over 2,400 species in about 460 genera in 33 families. The largest family is the Mantidae ("mantids") ...

(mantises) ***** Order

Alienoptera Alienopteridae is an extinct family of dictyopterans, known from the Early Cretaceous to the Eocene epoch. They are noted for their unusual combination of features not found in other dictyopterans. Description Alienopterid nymphs vary in morp ...

†(extinct) ***

Eumetabola Eumetabola is an unranked clade of Neoptera. Two large unities known as the Eumetabola and Paurometabola are probably from the adelphotaxa of the Neoptera after exclusion of the Plecoptera. The monophyly of these unities appears to be weakly jus ...

**** Order Miomoptera †(extinct) ****

Paraneoptera Paraneoptera or Acercaria is a Order (biology), superorder of insects which includes Psocodea, lice (Psocoptera, bark lice and Louse, true lice), thrips, and hemipterans, the true bugs. It also includes the extinct order Permopsocida, known from ...

***** Order

Psocodea Psocodea is a taxonomic group of insects comprising the bark lice, book lice and parasitic lice. It was formerly considered a superorder, but is now generally considered by entomologists as an order. Despite the greatly differing appearance of ...

(booklice, barklice,

lice Louse (: lice) is the common name for any member of the infraorder Phthiraptera, which contains nearly 5,000 species of wingless parasitic insects. Phthiraptera was previously recognized as an order, until a 2021 genetic study determined th ...

) ***** Superorder

Condylognatha Condylognatha or Panhemiptera is a monophyletic grouping (superorder) that contains Hemiptera (true bugs) and Thysanoptera (thrips). Condylognatha belongs to Paraneoptera, which include its sister group, lice (Psocodea). Taxonomy Hemiptera and ...

****** Order

Thysanoptera Thrips (order Thysanoptera) are minute (mostly long or less), slender insects with fringed wings and unique asymmetrical mouthparts. Entomologists have described approximately 7,700 species. They fly only weakly and their feathery wings are ...

(thrips) ****** Order

Hemiptera Hemiptera (; ) is an order of insects, commonly called true bugs, comprising more than 80,000 species within groups such as the cicadas, aphids, planthoppers, leafhoppers, assassin bugs, bed bugs, and shield bugs. They range in size from ...

(true bugs) ****

***** Superorder

Hymenopterida Hymenopterida is a superorder of holometabolous (metamorphosing) insects. As originally circumscribed, it included Hymenoptera and the orders in Panorpida (Mecoptera, Siphonaptera, Diptera, Trichoptera and Lepidoptera).Weaver J.S.IThe Evolutio ...

****** Order

Hymenoptera Hymenoptera is a large order of insects, comprising the sawflies, wasps, bees, and ants. Over 150,000 living species of Hymenoptera have been described, in addition to over 2,000 extinct ones. Many of the species are parasitic. Females typi ...

(

ant Ants are Eusociality, eusocial insects of the Family (biology), family Formicidae and, along with the related wasps and bees, belong to the Taxonomy (biology), order Hymenoptera. Ants evolved from Vespoidea, vespoid wasp ancestors in the Cre ...

bee Bees are winged insects closely related to wasps and ants, known for their roles in pollination and, in the case of the best-known bee species, the western honey bee, for producing honey. Bees are a monophyletic lineage within the superfamil ...

s, etc.) *****

Aparaglossata Aparaglossata is a clade of insects comprising all modern holometabolous insects except for Hymenoptera. The clade is named for one of its most recognizable synapomorphies (shared distinguishing feature); the absence of paraglossae. The clade is ...

******

Neuropteroidea Aparaglossata is a clade of insects comprising all modern holometabolous insects except for Hymenoptera. The clade is named for one of its most recognizable synapomorphies (shared distinguishing feature); the absence of paraglossae. The clade is ...

******* Superorder

Neuropterida The Neuropterida are a clade of holometabolous insects, sometimes placed at the superorder level. The clade contains the orders Neuroptera (lacewings, antlions), Megaloptera (alderflies, dobsonflies), and Raphidioptera (snakeflies), and includes ...

******** Order

Raphidioptera Snakeflies are a group of predatory insects comprising the order (biology), order Raphidioptera with two extant families: Raphidiidae and Inocelliidae, consisting of roughly 260 species. In the past, the group had a much wider distribution than i ...

(snakeflies) ******** Order

Megaloptera Megaloptera is an order of insects. It contains the alderflies, dobsonflies and fishflies, and there are about 300 known species. The order's name comes from Ancient Greek, from ''mega-'' (μέγα-) "large" + ''pteryx'' (πτέρυξ) "wi ...

(

alderflies Alderflies are megalopteran insects of the family Sialidae. They are closely related to the dobsonflies and fishflies as well as to the prehistoric Euchauliodidae. All living alderflies – about 66 species all together – are part of the subfa ...

, etc.) ******** Order

Neuroptera The insect order (biology), order Neuroptera, or net-winged insects, includes the lacewings, mantidflies, antlions, and their relatives. The order consists of some 6,000 species. Neuroptera is grouped together with the Megaloptera (alderflies, f ...

(net-veined insects) ******* Superorder

Coleopterida Coleopterida is a superorder of insects consisting of the orders Coleoptera and Strepsiptera. It is established as the sister group of Neuropterida based on phylogenetic analysis of DNA sequence data. The grouping is also supported by morphologic ...

******** Order

Coleoptera Beetles are insects that form the Taxonomic rank, order Coleoptera (), in the superorder Holometabola. Their front pair of wings are hardened into wing-cases, elytra, distinguishing them from most other insects. The Coleoptera, with about 40 ...

(beetles) ******** Order

Strepsiptera The Strepsiptera () are an order of insects with eleven extant families that include about 600 described species. They are endoparasites of other insects, such as bees, wasps, leafhoppers, Zygentoma, silverfish, and cockroaches. Females of most s ...

(twisted-winged parasites) ****** Superorder

Panorpida Panorpida or Mecopterida is a Superorder of Holometabola. The conjectured monophyly of the Panorpida is historically based on morphological evidence, namely the reduction or loss of the ovipositor and several internal characteristics, including ...

*******

Antliophora Panorpida or Mecopterida is a Superorder of Holometabola. The conjectured monophyly of the Panorpida is historically based on morphological evidence, namely the reduction or loss of the ovipositor and several internal characteristics, including ...

******** Mecopteroidea ********* Order

Mecoptera Mecoptera (from the Greek language, Greek: ''mecos'' = "long", ''ptera'' = "wings") is an Order (biology), order of insects in the superorder Holometabola with about six hundred species in nine Family (biology), families worldwide. Mecopterans a ...

(scorpionflies, etc.) ********* Order

Siphonaptera Flea, the common name for the order Siphonaptera, includes 2,500 species of small flightless insects that live as external parasites of mammals and birds. Fleas live by ingesting the blood of their hosts. Adult fleas grow to about long, are ...

(

flea Flea, the common name for the order (biology), order Siphonaptera, includes 2,500 species of small flightless insects that live as external parasites of mammals and birds. Fleas live by hematophagy, ingesting the blood of their hosts. Adult f ...

s) ******** Order

Diptera Flies are insects of the order Diptera, the name being derived from the Greek δι- ''di-'' "two", and πτερόν ''pteron'' "wing". Insects of this order use only a single pair of wings to fly, the hindwings having evolved into advance ...

(true

flies Flies are insects of the Order (biology), order Diptera, the name being derived from the Ancient Greek, Greek δι- ''di-'' "two", and πτερόν ''pteron'' "wing". Insects of this order use only a single pair of wings to fly, the hindwin ...

) ******** Order Protodiptera †(extinct) *******

Amphiesmenoptera Amphiesmenoptera is an insect superorder, established by S. G. Kiriakoff, but often credited to Willi Hennig in his revision of insect taxonomy for two sister orders: Lepidoptera (butterflies and moths) and Trichoptera (caddisflies). In 2017, ...

******** Order

Trichoptera The caddisflies (order Trichoptera) are a group of insects with aquatic larvae and terrestrial adults. There are approximately 14,500 described species, most of which can be divided into the suborders Integripalpia and Annulipalpia on the basis ...

(

caddisflies The caddisflies (order Trichoptera) are a group of insects with aquatic larvae and terrestrial adults. There are approximately 14,500 described species, most of which can be divided into the suborders Integripalpia and Annulipalpia on the basis ...

) ******** Order

Lepidoptera Lepidoptera ( ) or lepidopterans is an order (biology), order of winged insects which includes butterflies and moths. About 180,000 species of the Lepidoptera have been described, representing 10% of the total described species of living organ ...

(

butterflies Butterflies are winged insects from the lepidopteran superfamily Papilionoidea, characterized by large, often brightly coloured wings that often fold together when at rest, and a conspicuous, fluttering flight. The oldest butterfly fossi ...

moth Moths are a group of insects that includes all members of the order Lepidoptera that are not Butterfly, butterflies. They were previously classified as suborder Heterocera, but the group is Paraphyly, paraphyletic with respect to butterflies (s ...

References

{{Authority control Arthropod subclasses Dicondylia Extant Pennsylvanian first appearances Insect taxonomy