Pontia

Balletto, Emilio, Barbero, Francesca, Bonelli, Simona, Casacci, Luca P. & Dapporto, Leonardo, 2020, Stabilisation of some names of European butterflies (Lepidoptera: Pieridae) in their prevailing usage, Zootaxa 4780 (2), pp. 387-395 : 387

Genus Pontia [Fabricius], 1807

The genus Pontia (s.str.) was considered for a long time to include only two Palaearctic species, i.e. P. daplidice (Linnaeus, 1758) and P. glauconome Klug, 1829 , which are more or less broadly distributed also in parts of the African continent. In the early 1980s, however, electrophoretic studies by Geiger & Scholl (1982a, b) and by Geiger et al. (1988) suggested that under the first of these names were included two separate species i.e. P. daplidice and P. edusa (Fabricius, [1777]) (see Wagener 1988 for a discussion of nomenclatural aspects). The sequence analysis of the ‘barcoding fragment’ of the COI mitochondrial gene conducted by John et al. (2013) concurred with the results from electrophoretic studies and showed that the distribution of P. daplidice is principally S.W. European, while P. edusa flies from C.E. Europe to Japan (see also Dapporto et al. 2019 for a large COI dataset). At least in one case, the two species stably occur together in a restricted area in N.W. Italy, where they form a narrow hybridization belt ( Porter et al. 1997), while some other cases of spatial overlap (e.g. in Sicily, S.E. Turkey and Israel) may perhaps be caused by migrant individuals. Since the two species are morphologically indistinguishable (characters listed in Wagener 1988 and by Hesselbarth et al. 1995 are not fully reliable), the usage of at least one species-group name needs to be fixed.