Synonym

A synonym is a scientific name applied in whole or in part to a particular taxon but is not the correct accepted name (in a particular taxonomic classification) for the taxon to which it refers.  Synonyms arise for several reasons.  Because of changes in the scientific understanding of taxonomic relationships, two species (or taxa of higher or lower rank, as well) may be merged.  This will make one of the two names a synonym of the other.  Sometimes a scientific author may be unaware that someone else has already published a name for a species.  A genus may be split into two or more smaller genera.  The TDC attempts to list the most commonly occurring synonyms and to give the corresponding correct accepted name. Two common nomenclatural conventions are important to understand when considering synonymy:  The "auct. non [Author]" designation indicates that a name has been used by various authors in the sense of the synonym under consideration but not in the strict sense of the name (based on the original publication by the original "Author"), which refers to a different species.  For example, names based on types of European plants have sometimes been misapplied in this way to American plants.  The Latin phrase literally means "of authors, not [Author]," where "Author" refers to the author of the original name, in its strict sense. The "pro parte" designation (abbreviated "p.p." following the author of a scientific name, meaning "in part") indicates that the name (as a synonym) has been used in a broad concept to include the correct, currently accepted name under which it is listed, as well as at least one other correct, currently accepted name.  The same "pro parte" name might thus be expected to appear as a synonym in several places in the Synthesis.  Such concepts arise from taxonomic study that produces more precise circumscriptions, clarifications of typification, or other clarifications of application.