In insect anatomy the arista is a simple or variously modified

apical Apical means "pertaining to an apex". It may refer to: *Apical ancestor, refers to the last common ancestor of an entire group, such as a species (biology) or a clan (anthropology) *Apical (anatomy), an anatomical term of location for features loc ...

or subapical bristle, arising from the third antennal segment. It is the

evolution Evolution is change in the heritable characteristics of biological populations over successive generations. These characteristics are the expressions of genes, which are passed on from parent to offspring during reproduction. Variation ...

ary remains of antennal segments, and may sometimes show signs of segmentation. These segments are called aristameres. The arista may be bare and thin, sometime appearing no more than a simple bristle;

pubescent The adjective pubescent may describe: * people or animals undergoing puberty * plants that are hairy, covered in trichomes * insects that are covered in setae In biology, setae (singular seta ; from the Latin word for "bristle") are any of a ...

, covered in short hairs; or plumose, covered in long hairs. The presence of an arista is a feature of the

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 advanced ...

(flies) suborder

Brachycera The Brachycera are a suborder of the order Diptera. It is a major suborder consisting of around 120 families. Their most distinguishing characteristic is reduced antenna segmentation. Description A summary of the main physical characteristics i ...

and may be especially well-developed in some species. It is also present in some members of

Hemiptera Hemiptera (; ) is an order (biology), order of insects, commonly called true bugs, comprising over 80,000 species within groups such as the cicadas, aphids, planthoppers, leafhoppers, Reduviidae, assassin bugs, Cimex, bed bugs, and shield bugs. ...

(true bugs), specifically in the suborder

Auchenorrhyncha 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 ot ...

. The arista is often covered in multiple kinds of

sensilla A sensillum (plural ''sensilla'') is an arthropod sensory organ protruding from the cuticle of exoskeleton, or sometimes lying within or beneath it. Sensilla appear as small hairs or pegs over an individual's body. Inside each sensillum there are ...

, or sense organs, such as chemo, hygro, and thermoreceptors, which allow the insects to detect changes in their environment.

References

Insect anatomy Brachycera {{insect-anatomy-stub Auchenorrhyncha