Stria density and count in centric diatoms


Transapical axis

One of possibly many scientific names belonging to a taxon. Two types of 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 International Code of Nomenclature for algae, fungi, and plants (ICN). 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 objective synonyms. Expert contributors and reviewers determine the relevant objective 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 subjective synonyms under the heading, REPORTED AS. This heading also includes errors in identification published in various floras.


McNeill J., Barrie, F.R., Buck, R., Demoulin, V., Greuter, W., Hawksworth, D.L., Herendeen, P.S., Knapp, S., Marhold, K., Prado, J., Prud'homme Van Reine, W.F., Smith, G.F., Wiersema, J.H. (2012). International Code of Nomenclature for algae, fungi, and plants (Melbourne Code) . Regnum Vegetabile 154. ISBN 978-3-87429-425-6.