Abstract
The amplification of a part of the COI mitochondrial gene, using the universal arthropod primer or primers derived from it, was successful only in less than half of the populations under study. In contrast, amplification of a part of the 12S srRNA gene, worked very well in all the populations.
Cyclops abyssorum, a morphologically and ecologically variable species, showed very low between-population sequence polymorphism. The ecotypes “praealpinus“, “divulsus“ and “tatricus“ seem to lack a species or subspecies status.
They are likely to be, as Einsle supposed, morphological variations only. Populations of C. strenuus, another widespread species, were also genetically uniform.
The ecological valence of C. singularis, described from temporary ponds in southern Germany, is broader than expected; the species may occur in permanent water bodies (e.g., the hypolimnion of the deep Slapy reservoir and shallow permanent ponds).