fascicularis

Fascicularis is a Latin adjective used in the scientific names of various organisms. The term derives from fasciculus, meaning a small bundle or cluster, and is typically applied to indicate a fascicled or bundle-like arrangement of structures such as leaves, hairs, or fibers. In taxonomy, fascicularis is an epithet rather than a single taxon, appearing in the binomials of diverse genera across animals and plants.

One of the best-known examples is Macaca fascicularis, the crab-eating macaque or long-tailed macaque, a primate native to Southeast Asia. It occupies a wide range of habitats, including forests, mangroves, and agricultural areas, and is notable for its adaptability and complex social behavior. The species is frequently used in biomedical research and ecological studies due to its close phylogenetic relationship to humans and its ubiquity in the region.

The epithet fascicularis is applied in other taxa as well, reflecting morphological impressions rather than indicating a close relationship among groups. In plants, for instance, fascicularis may describe fascicles or bundles of leaves, flowers, or other structures.

Because fascicularis is an epithet rather than a stand-alone taxon, it does not by itself identify a single species. Its use spans multiple genera and kingdoms, illustrating how Latin descriptors convey characteristic features in a broad, descriptive sense within scientific naming.