Millipedes

Definition

A class of myriapod arthropods (Diplopoda) characterized by two pairs of jointed legs per body segment, resulting from the fusion of adjacent segments during development. Millipedes typically possess elongated, cylindrical or flattened bodies with 20 or more segments, slow movement, and detritivorous feeding habits. Unlike centipedes, they lack venomous forcipules and are generally non-predatory. The class contains approximately 12,000 described species across 16 orders, ranging from minute soil-dwellers to the recently discovered Eumillipes persephone, which holds the record for most legs (over 1,300) among known animals.

Etymology

From Latin 'mille' (thousand) + 'pes' (foot), though no species actually possessed 1,000 legs until 2020.

Example

The greenhouse millipede (Oxidus gracilis) is a common introduced species in North American gardens, where its populations can reach nuisance densities in moist leaf litter.

Synonyms

• Diplopoda

Related Terms

• Centipedes
• myriapods
• Detritivore
• arthropod
• chilopods
• diplopods
• pill millipede

Usage Notes

The common name 'millipede' is often misapplied to any multi-legged arthropod; specialists reserve it for Diplopoda specifically. Contrast with centipedes (Chilopoda), which have one leg pair per segment, are faster, and possess venomous forcipules. The class is the largest within Myriapoda by species diversity. Some authors use 'diplopod' as a more precise technical alternative.