subfamilia

Subfamilia, or subfamily, is a taxonomic rank used in biological classification. It sits below the family and above the tribe (in many animal classifications) or above the tribe in plant systems. The rank groups together related genera that share characteristic traits and evolutionary history, providing a way to organize large families into smaller, more coherent units.

Nomenclature and scope vary by code. In zoology, subfamily names typically end with the suffix -inae (for example, Homininae). In botany, the equivalent rank is -oideae (for example, Papilionoideae, Solanoideae). The plural forms follow the same pattern: -inae for animals and -oideae for plants. Subfamilies may be further divided into tribes and then into genera and species.

Not all groups use subfamilies; in some classifications the rank is optional or replaced by unranked clades. In practice, subfamilies may be subdivided into tribes, or directly into genera if a tribe is not employed. Molecular phylogenetics has reshaped many subfamilial boundaries, leading to reclassification or redefinition of groups in some lineages.

Examples illustrate the range of usage. Homininae is a subfamily within Hominidae, including humans and close relatives. Asteroideae is a large subfamily of Asteraceae. Papilionoideae is a subfamily within Fabaceae, and Solanoideae is a subfamily within Solanaceae. These examples show how subfamilies help organize diversity into meaningful evolutionary lineages while accommodating variation across different kingdoms.