Loricate choanoflagellates (Acanthoecida) from warm water seas. IV. Cosmoeca Thomsen

Aided by an extensive collection of specimens from warm water seas, it has been possible to revisit the loricate choanoflagellate genus Cosmoeca. While the generic type C. norvegica and also C. ventricosa sensu stricto have been described from temperate North Atlantic realms and share a cosmopolitan distribution, the remaining species and morphotypes of Cosmoeca are largely confined to warmer waters. The new data broadly validates the initial circumscription of species of Cosmoeca. The persisting taxonomic puzzle with respect to C. ventricosa, which in addition to the core type accommodates no less than five different morphotypes (form A-E), has been further elucidated. The Cosmoeca paper is part of a ‘monographic’ series of warm water loricate choanoflagellate contributions in progress, where the aim is to provide the best possible account of warm water species diversity, based on traditional light and electron microscopical techniques, as a tool for future identification work based on microscopy, and in support of the work in progress with establishing a quality assured molecular tool for future recognition of diversity.