Molecular taxonomic parameters

Abstract

The parameters in place for the circumscription of taxonomic ranks increase with the description of lower ranks; only one or a few, mostly genomic properties, for phyla, classes and orders, while those for families, genera and, above all, for species, are described with increasing complexity, including molecular, chemotaxonomic, morphological and biochemical properties. Even the attempt to list a few examples for species-rich genera or for a phylogenetically diverse range of taxa would go beyond the scope of this communication. Rather, the presently applied molecular approaches for delineation should be revisited here. For a broad overview on the use of the wide spectrum of phenotypic methods recommended today the reader is referred to a recent publication by Tindall et al.