Capitate

Definition

Having a knobbed or head-like swelling at the apex; terminating in a rounded, enlarged tip. In arthropod morphology, describes antennae, sensilla, setae, or other appendages that end in a distinct club-shaped or globular enlargement.

Etymology

Latin capitatus, from caput 'head'

Example

The capitate antennae of scarab beetles (Scarabaeidae) form a lamellate club of plate-like segments that can be fanned out to detect pheromones; similarly, capitate sensilla on the tarsi of some insects function as contact chemoreceptors.

Synonyms

• Clavate

Related Terms

• Clavate
• Lamellate
• Sensillum
• seta
• antenna
• Distal

Usage Notes

Distinguished from 'clavate' (gradually club-shaped) by implying a more abrupt, distinct terminal swelling. In entomology, most commonly applied to antennae (capitate antennae = clubbed antennae) and mechanosensory or chemosensory structures. Not to be confused with the capitate bone of the mammalian wrist, which shares only the Latin root.