The Exopterygota ( Ancient Greek ''ἔξω'' (éxō, “outside”) + ''πτερόν'' (pterón, “wing”) +

New Latin New Latin (also called Neo-Latin or Modern Latin) is the revival of Literary Latin used in original, scholarly, and scientific works since about 1500. Modern scholarly and technical nomenclature, such as in zoological and botanical taxonomy a ...

''-ota'' (“having”)), also known as Hemipterodea, are a

superorder Order ( la, ordo) is one of the eight major hierarchical taxonomic ranks in Linnaean taxonomy. It is classified between family and class. In biological classification, the order is a taxonomic rank used in the classification of organisms and ...

of insects of the subclass Pterygota in the

infraclass In biological classification, class ( la, classis) is a taxonomic rank, as well as a taxonomic unit, a taxon, in that rank. It is a group of related taxonomic orders. Other well-known ranks in descending order of size are life, domain, kingdo ...

Neoptera, in which the young resemble adults but have externally developing wings. They undergo a modest change between immature and adult, without going through a pupal stage. The nymphs develop gradually into adults through a process of moulting. The Exopterygota are a highly diverse insect superorder, with at least 130,000 living species divided between 15

orders Order, ORDER or Orders may refer to: * Categorization, the process in which ideas and objects are recognized, differentiated, and understood * Heterarchy, a system of organization wherein the elements have the potential to be ranked a number of ...

. They include

cockroach Cockroaches (or roaches) are a paraphyletic group of insects belonging to Blattodea, containing all members of the group except termites. About 30 cockroach species out of 4,600 are associated with human habitats. Some species are well-known as ...

es,

termite Termites are small insects that live in colonies and have distinct castes (eusocial) and feed on wood or other dead plant matter. Termites comprise the infraorder Isoptera, or alternatively the epifamily Termitoidae, within the order Blattode ...

s, grasshoppers,

thrip Thrips ( order Thysanoptera) are minute (mostly long or less), slender insects with fringed wings and unique asymmetrical mouthparts. Different thrips species feed mostly on plants by puncturing and sucking up the contents, although a few are ...

lice Louse ( : lice) is the common name for any member of the clade Phthiraptera, which contains nearly 5,000 species of wingless parasitic insects. Phthiraptera has variously been recognized as an order, infraorder, or a parvorder, as a result o ...

and

stick insect The Phasmatodea (also known as Phasmida, Phasmatoptera or Spectra) are an order of insects whose members are variously known as stick insects, stick-bugs, walking sticks, stick animals, or bug sticks. They are also occasionally referred to as ...

s, among many other types of insects. They are distinguished from the Endopterygota (or Holometabola) by the way in which their wings develop. Endopterygota (meaning literally "internal winged forms") develop wings inside the body and undergo an elaborate metamorphosis involving a pupal stage. Exopterygota ("external winged forms") develop wings on the outside of their bodies without going through a true pupal stage, though a few have something resembling a pupa (e.g.,

Aleyrodidae 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. Description and taxonomy The A ...

). Ephemeroptera (mayflies) and Odonata (dragonflies and damselflies) also have gradual wing development, this being a plesiomorphic trait. These two orders belong to the infraclass

Palaeoptera 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 Neopt ...

however, which is not included in Neoptera. As opposed to Neoptera, they cannot fold their wings over their back in the

horizontal plane In astronomy, geography, and related sciences and contexts, a '' direction'' or '' plane'' passing by a given point is said to be vertical if it contains the local gravity direction at that point. Conversely, a direction or plane is said to be ho ...

, only vertically (as damselflies do) if at all.

Systematics

Traditionally Exopterygota included all neopterans that show

incomplete metamorphosis Hemimetabolism or hemimetaboly, also called incomplete 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 certa ...

. More recently, there is increasing debate about how to subdivide the Exopterygota, and the Neoptera in general. It is realized that some presumed Exopterygota may in fact be basal neopterans, making the superorder paraphyletic. Here is a complete list of living and extinct orders of "exopterygotes", with some proposed subdivisions: Superorder Exopterygota ''

sensu stricto ''Sensu'' is a Latin word meaning "in the sense of". It is used in a number of fields including biology, geology, linguistics, semiotics, and law. Commonly it refers to how strictly or loosely an expression is used in describing any particular co ...

'' *

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

(Extinct) *

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) * Protorthoptera (Extinct) * Plecoptera (stoneflies) * Embioptera (webspinners) *

Zoraptera The insect 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 and without eye ...

(angel insects) * Dermaptera (earwigs) * Orthoptera ( grasshoppers, etc.) Proposed superorder Dictyoptera * Phasmatodea (stick insects – tentatively placed here) *

Notoptera The wingless insect order Notoptera, a group first proposed in 1915, had been largely unrecognized since its original conception, until resurrected in 2004. As now defined, the order comprises five families, three of them known only from fossils ...

(ice-crawlers and gladiators – tentatively placed here) *

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

(cockroaches and termites) * Mantodea (mantids) Proposed superorder

Paraneoptera Paraneoptera or Acercaria is a superorder of insects which includes lice ( bark lice and true lice), thrips, and hemipterans, the true bugs. It also includes the extinct order Permopsocida, known from fossils dating from the Early Permian to t ...

* Psocoptera (booklice, barklice) *

Thysanoptera Thrips ( order Thysanoptera) are minute (mostly long or less), slender insects with fringed wings and unique asymmetrical mouthparts. Different thrips species feed mostly on plants by puncturing and sucking up the contents, although a few are ...

(thrips) *

Phthiraptera Louse ( : lice) is the common name for any member of the clade Phthiraptera, which contains nearly 5,000 species of wingless parasitic insects. Phthiraptera has variously been recognized as an order, infraorder, or a parvorder, as a result o ...

(

) *

Hemiptera 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 to aroun ...

(true bugs)

References

{{Taxonbar, from=Q591127 Insect superorders Paraphyletic groups Neoptera