In biology, a holotype is the single example (either a physical specimen or an illustration) that is used to define a taxon (such as species or sub-species). Any examples of the taxon that are not the holotype but are used in the initial description of the species are referred to as paratypes. The holotype plus the paratypes are collectively know as a type series.
The paratype may include some variations on the species form, but is is different from the allotype, the specimen that exemplifies the opposite sex of the holotype. Paratypes may include variations in coloration, age, or seasonal changes, or may simply provide evidence that the holotype really is a central example of the new species.