How common are dot-like distributions? Taxonomical oversplitting in western European Agrodiaetus (Lepidoptera: Lycaenidae) revealed by chromosomal and molecular markers

Approximately 50 taxa of butterflies in Western Europe have been described as new species or elevated to the level
of species during the last 40 years. Many, especially those belonging to the genus Agrodiaetus, have unusually
localized, ‘dot-like’ distributional ranges. In the present study, we use a combination of chromosomal and molecular
markers to re-evaluate the species status of Agrodiaetus distributed west of the 17th meridian. The results
obtained do not support the current designations of Agrodiaetus galloi, Agrodiaetus exuberans, and Agrodiaetus
agenjoi as endemic species with highly restricted distribution ranges, but indicate that these taxa are more likely
to be local populations of a widely distributed species, Agrodiaetus ripartii. Agrodiaetus violetae is shown to be a
polytypic species consisting of at least two subspecies, including Agrodiaetus violetae subbaeticus comb. nov. and
Agrodiaetus violetae violetae. Agrodiaetus violetae is genetically (but not chromosomally) distinct from Agrodiaetus
fabressei and has a wider distribution in southern Spain than previously believed. Agrodiaetus humedasae from
northern Italy is supported as a highly localized species that is distinct from its nearest relatives. We propose a
revision of the species lists for Agrodiaetus taking these new data into account. The results reported in the present
study are relevant to animal conservation efforts in Europe because of their implications for IUCN Red List
priorities.