Taxonomic diagnosis of Dicyrtomina ornata and D.saundersi (Collembola: Dicyrtomidae) and analysis of their population genetic structure

The taxonomic validity of two presumed species of the collembolan genus Dicyrtomina was evalu- ated by using allozyme electrophoresis. Twenty-one loci were screened in seven populations assigned to D. ornata and eight populations assigned to D. saundersi. The presence of loci fixed for alternative allelic patterns in sympatric populations demonstrated that the two species are reproduc- tively isolated, therefore confirming their specific status. Average genetic distance between popula- tions of the two species was D=0.714. Populations of D. ornata were more differentiated from one another with respect to those of D. saundersi, which showed higher levels of gene flow.