Diplura

Definition

A class (or historically order) of small, pale, eyeless hexapods within the subphylum Hexapoda, characterized by the presence of two caudal cerci (appendages) and the absence of a median terminal filament—hence "double tail." Diplurans are elongate, soft-bodied, and entognathous (mouthparts withdrawn into a pouch), with filiform antennae. They inhabit moist soil, leaf litter, and decaying organic matter where they feed on detritus and small invertebrates. The group comprises approximately 800 described species in two principal superfamilies: Campodeoidea (slender, fast-moving campodeids) and Japygoidea (more robust japygids with forceps-like cerci used in predation and defense). Diplura is one of the four major lineages of hexapods, alongside Collembola, Protura, and Insecta.

Etymology

From Greek diploos (double) + oura (tail), referring to the paired cerci.

Example

Campodea staphylinus, a widespread European dipluran, is frequently encountered in soil samples and serves as an indicator of stable, undisturbed litter layers.

Synonyms

• two-pronged bristletails
• dipleurans

Related Terms

• Entognatha
• Collembola
• Protura
• Thysanura
• Cerci
• hexapod
• soil mesofauna
• campodeid
• japygid

Usage Notes

Taxonomic rank has been unstable: treated as an order within class Entognatha in some systems, or as a class within subphylum Hexapoda in others. The name Diplura is also a homonym for a genus of mygalomorph spiders (family Dipluridae), but in entomological contexts refers exclusively to the hexapod group. Distinguished from Thysanura (silverfish and firebrats) by the absence of the median caudal filament; distinguished from Protura by possession of antennae and cerci. The forceps-like cerci of japygids can deliver a noticeable pinch, while campodeids have slender, thread-like cerci.