serrula

Serrula is a term from Latin used in scientific description to denote a small, saw-like edge or projection on a structure. Derived from the word serra meaning “saw,” with the diminutive suffix -ula, serrula functions as a descriptive descriptor rather than a formal taxonomic name in most contexts.

In botany, serrula may describe a leaf margin that is finely serrate at a micro scale, producing tiny tooth-like projections that are smaller than those of a fully serrate edge. It can also appear in descriptions of seed coats, bracts, or other plant parts where minute dentitions occur. The term helps differentiate very fine serrations from broader or more pronounced margins.

In zoology and paleontology, serrula similarly designates small serrations on various surfaces, including mandibles, labial or other mouthparts, or shell and plate margins. In insects, serrulae can refer to rows of tiny teeth that contribute to processing food or interacting with the environment. In other groups, the presence of serrulate or serrulate-like structures may be described with the same root concept, emphasizing a diminutive serration pattern.

As a morphological descriptor, serrula is distinct from related terms such as serrate (coarser teeth) and serrulate (very fine teeth). While there have been occasional uses of Serrula as a genus name in historical or obscure taxonomic contexts, such usages are not widely recognized in modern classifications and the term is primarily descriptive.

See also: serration, serrate, serrulate, serra.