Names, diagnoses and ‘Dead Names’: the case of Synedra pelagica

The case of Synedra pelagica Hendey is discussed in terms of its nomenclature, the taxonomic implications of priority issues and its characterization. Application of replacement names for specific epithets is reasonably straightforward as it is governed by the ICN – conditions for valid publication of any taxonomic name can be satisfied even if no one can subsequently identify the taxon. The lack of clear diagnostic characters, as opposed to a description, can obscure what the name actually represents. These issues are briefly discussed with Synedra pelagica in mind.