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To split or not to split, that's the question - to paraphrase an overburdened expression. My question is: on what grounds is the splitting done? It surely is a sign of my total ignorance, but I wonder what species criterion is used. Since it seems to me very difficult to establish whether two 'forms' cross in the wild, I guess splitting is much based on morphological criteria - especially those of the genitalia. But morphological differences in the genitalia need not make copulation impossible - and thus genetic isolation may not coincide with morphological differentiation. If a morphological difference is found, is then subsequently looked for a actual mating barrier in the field? If not, I would hesitate to attach species status to the morph. Currently, the species level is much inflated - at least this is so in butterflies. Here, all kind of bona fide subspecies are rased to specieshood, a prime example of rank inflation. In fact, one wonders whether the species concept itself is undergoing some major change!