quinqueradiata

Quinqueradiata is a taxonomic epithet used in the scientific names of various organisms. It is not a standalone taxon but signals a characteristic described by the namer. The name derives from Latin quinque, meaning five, and radiata, meaning radiating or ray-like, typically indicating a five-armed or five-rayed form.

In zoological practice, quinqueradiata has appeared in several species across different groups, most commonly among echinoderms such as starfish, where pentaradial symmetry yields five arms. The epithet is descriptive rather than classificatory and may be applied to species that differ in genus and higher relationships. Because the same epithet can appear in unrelated taxa, the full binomial name (genus plus species) is required to identify a taxon unambiguously. Taxonomic revisions can alter or synonymize species with this epithet.

Some universals: The epithet reflects morphology rather than evolutionary kinship; instances of five-rayed forms have evolved multiple times across marine invertebrates as well as other groups. However, quinqueradiata alone does not convey taxonomic rank or phylogenetic position.

See also: binomial nomenclature, Latin in scientific naming, pentaradial symmetry, Asteroidea.