type species the nominal species that is the name-bearing type of a nominal genus or subgenus.
type genus the nominal genus that is the name-bearing type of a nominal family-group taxon.
type series all those specimens included by the author in a taxon's formal description, unless the author explicitly or implicitly excludes them as part of the series.
type host (or symbiotype) is used to indicate the host organism from which the type specimen of a parasite was obtained.
holotype A single specimen is clearly designated in the original description of a species, typically placed in a major museum, or similar well-known public collection, so that it is freely available for later examination by other biologists.
paratype When the original description designated a holotype, there may still be additional specimens listed in the type series and those are termed paratypes. These are not name-bearing types.
neotype a specimen later selected to serve as the single type specimen when an original holotype has been lost or destroyed or where the original author never cited a specimen.
syntype any one of two or more specimens that is listed in a species description where no holotype was designated; historically, syntypes were often explicitly designated as such, and under the present ICZN this is a requirement, but modern attempts to publish species description based on syntypes are generally frowned upon by practicing taxonomists, and most are gradually being replaced by lectotypes. Those that still exist are still considered name-bearing types.
lectotype a specimen later selected to serve as the single type specimen for species originally described from a set of syntypes. A lectotype is a kind of name-bearing type. When a species was originally described on the basis of a name-bearing type consisting of multiple specimens, one of those may be designated as the lectotype. A lectotype is the single specimen selected from among the syntypes to serve as the only name-bearing type specimen, and is formally designated as such. Having a single name-bearing type reduces the potential for confusion, especially considering that it is not uncommon for a series of syntypes to contain specimens of more than one species.
paralectotype any additional specimen from among a set of syntypes, after a lectotype has been designated from among them. These are not name-bearing types.
hapantotype in Protistans where the type consists of two or more specimens of "directly related individuals representing distinct stages in the life cycle"; these are collectively treated as a single entity, and lectotypes cannot be designated from among them.
ergatotype a specimen selected to represent a worker member in hymenopterans which have polymorphic castes.
type illustration have also been used by zoologists, as in the case of the Réunion Parakeet, which is known only from historical illustrations and descriptions.
Recently, some species have been described where the type specimen was released alive back into the wild, such as the Bulo Burti Boubou (a bushshrike), described as Laniarius liberatus, in which the species description included DNA sequences from blood and feather samples. Assuming there is no future question as to the status of such a species, the absence of a type specimen does not invalidate the name, but it may be necessary in the future to designate a neotype for such a taxon, should any questions arise. However, in the case of the bushshrike, ornithologists have argued that the specimen was a rare and hitherto unknown color morph of a long-known species, using only the available blood and feather samples. While there is still some debate on the need to deposit actual killed individuals as type specimens, it can be observed that given proper vouchering and storage, tissue samples can be just as valuable even in case disputes about the validity of a species arise.
fixation the declaration of a name-bearing type, whether by original or subsequent designation.
type species (the term "genotype" was once used for this but has been abandoned because the word has been co-opted for use in genetics and is much better known in that context)
allotype a specimen of the opposite sex to the holotype, designated from among paratypes. It was also formerly used for a specimen that shows features not seen in the holotype of a fossil.
