Inbiology, asubgenus (plural:subgenera) is ataxonomic rank directly belowgenus.
In theInternational Code of Zoological Nomenclature, a subgeneric name can be used independently or included in aspecies name, in parentheses, placed between thegeneric name and thespecific epithet: e.g. thetiger cowry of the Indo-Pacific,Cypraea (Cypraea)tigrisLinnaeus, which belongs to the subgenusCypraea of the genusCypraea. However, it is not mandatory, or even customary, when giving the name of a species, to include the subgeneric name.
In theInternational Code of Nomenclature for algae, fungi, and plants (ICNafp), the subgenus is one of the possible subdivisions of a genus. There is no limit to the number of divisions that are permitted within a genus by adding the prefix "sub-" or in other ways as long as no confusion can result.[1] The secondary ranks ofsection andseries are subordinate to subgenus.[1] An example isBanksia subg.Isostylis, a subgenus of the large Australian genusBanksia.[2] The ICNafp requires an explicit "connecting term" to indicate the rank of the division within the genus.[3] Connecting terms are usually abbreviated, e.g. "subg." for "subgenus", and are not italicized.
In zoological nomenclature, when a genus is split into subgenera, the originally described population is retained as the "nominotypical subgenus" or "nominate subgenus", which repeats the same name as the genus. For example,Panthera (Panthera)pardus, aleopard. In botanical nomenclature the same principle applies, although the terminology is different. Thus the subgenus that contains the original type of the genusRhododendron isRhododendron subg.Rhododendron. Such names are called "autonyms".[4]