Apterygote

Definition

An insect that lacks wings throughout its life and whose lineage has never evolved wings; historically treated as a group (Apterygota) of primitive wingless insects including silverfish, firebrats, and jumping bristletails. The term describes a grade of organization rather than a clade, as winglessness arose independently in different lineages and some apterygotes are more closely related to winged insects than to other apterygotes.

Etymology

From Greek a- (without) + pteryx (wing)

Example

The jumping bristletail Machilis is a classic apterygote: it bears paired abdominal appendages called styli and retains the ancestral condition of lacking wings entirely, unlike secondarily wingless insects such as fleas or lice.

Synonyms

• apterygote insect
• primarily wingless insect

Related Terms

• apterygota
• Archaeognatha
• Zygentoma
• Pterygote
• Dicondylia
• paraphyly
• Silverfish
• bristletail
• styli
• secondarily wingless

Usage Notes

Distinguished from 'secondarily wingless' insects (fleas, lice, worker ants, etc.) whose ancestors possessed wings. The group Apterygota is paraphyletic and not recognized in modern phylogenetic classification; Archaeognatha and Zygentoma are treated as separate basal lineages. The term remains useful descriptively for wingless insects with primitively wingless morphology.