Glossary

A synonym, in taxonomy, is another scientific name for the correct name of a taxon (Turland 2013 Chapter 6). Homotypic and heterotypic synonyms are considered here. Homotypic synonyms are based on the exact same type specimen, or holotype. Homotypic synonyms are declared through a "nomenclatural act", that is, published in the scientific literature following the formal rules of the ICN (Turland 2018). For example, Achnanthes minutissima was transferred to the genus Achnanthidium and renamed Achnanthidium minutissimum. These two names are homotypic, nomenclatural, or objective, synonyms.

Heterotypic synonyms are based on different type specimens. These synonyms rely on the opinions of taxonomists rather than on the formal, nomenclatural rules. For example, Gomphonema louisiananum was first described by Kalinsky (1984). Later, this same diatom was described as Gomphonema patrickii by Kociolek and Stoermer (1995), using a different type specimen. These two names are heterotypic, or subjective, synonyms.

This web flora emphasizes homotypic synonyms. Expert contributors and reviewers determine the relevant homotypic synonyms to include on each species page and list them under the heading, SYNONYMS. We consider the relevant synonyms to be those that analysts might typically encounter. We also include names that we consider to be heterotypic synonyms under the heading, REPORTED AS. This heading also includes errors in identification published in various floras.

The glossary of the ICN may be found on-line by searching for "icn glossary".

See also basionym.