Dentition

Definition

The characteristic arrangement, type, number, and morphological structure of teeth or tooth-like structures in an organism's mouth or mouthparts. In arthropods, refers to the sclerotized projections, denticles, or cusps on chewing mouthparts (mandibles, maxillae), chelicerae, or other feeding appendages, often diagnostic for species identification and reflecting dietary specialization.

Etymology

Latin dens, dentis (tooth) + -ition (condition or state)

Example

The dentition of solifuges (sun spiders) features a distinctive pair of massive, curved cheliceral teeth used to crush prey, with species-specific tooth counts and arrangements used in taxonomy. Similarly, the mandibular dentition of carabid beetles varies from sharp, acute teeth in predatory species to blunt, molar-like cusps in granivores.

Synonyms

• tooth armature
• dental formula (when numerical)

Related Terms

• Chelicera
• Mandible
• Maxilla
• denticle
• molar area
• incisor
• Trochanter
• mouthpart morphology
• trophi

Usage Notes

In entomology and arachnology, 'dentition' typically describes macroscopic teeth on sclerotized mouthparts rather than microscopic cuticular projections. The term is more commonly applied to chelicerates and insects with well-developed chewing mandibles; for fluid-feeding insects with stylets, 'armature' or 'serration' is often preferred. Dental formulas (e.g., 3/3, 2/1) are rarely used in arthropod taxonomy compared to mammalian systematics, where they are standard.