SUBGENUS

In biology, a 'subgenus' is a taxon at a rank directly below genus. See rank (botany) and rank (zoology).
In zoology, a subgeneric name can be used independently or included in a species name, in parentheses, placed between the generic and specific name: e.g. the Tiger Cowry of the Indo-Pacific, ''Cypraea (Cypraea) tigris'' Linnaeus, which belongs to the subgenus ''Cypraea'' of the genus ''Cypraea''. However, it is not mandatory, or even customary, when giving the name of a species, to include the subgeneric name.
Note also that a name included in brackets is also sometimes used to indicate differences of taxonomic opinion, e.g. the Northern Gannet, ''Sula'' (''Morus'') ''bassana'' where it means that some taxonomists treat the species in the genus ''Sula'', while others split it off into a separate genus ''Morus''.