Moniliform

Definition

Having a cylindrical form with regular, bead-like constrictions or swellings along its length; resembling a string of beads or sausages. In arthropod morphology, the term describes antennae, palps, or other appendages composed of globular segments separated by narrow joints, as seen in many beetles, earwigs, and certain spiders. The condition contrasts with filiform (thread-like, uniform), clavate (clubbed), or serrate (saw-toothed) forms.

Etymology

From Latin monile (necklace, string of beads) + -form (shaped like)

Example

The moniliform antennae of the hide beetle Dermestes maculatus consist of eleven segments, each globose and distinctly constricted at the intersegmental membranes, giving the appendage its characteristic beaded appearance useful for species identification.

Synonyms

• moniliformous
• beaded

Related Terms

• Filiform
• Clavate
• serrate
• geniculate
• antenna
• palp
• segmentation
• annulated

Usage Notes

Applied primarily to segmented appendages and certain body regions; distinguish from 'annulated' (ringed but not necessarily swollen) and 'moniliformis' (a specific epithet in taxonomy, not the adjective). The term is absolute in description but relative in degree—some antennae are strongly moniliform, others weakly so.