Laothoe populi subsp. iberica Eitschberger, Danner & Surholt, 1990

SYN. & STAT. REV. Eitschberger, Danner & Surholt, 1990, Atalanta 20: 262. (Laothoe) HOLOTYPE ♂ Spain: Granada, Alfacar, 1200-1500m, 15 16.v.1969 (U. & F. Eitschberger) [coll. Eitschberger]. Proposed as a subspecies of Laothoe populi. Synonymized with the nominotypical subspecies by Pittaway, 1993, The hawkmoths of the Western Palaearctic: 102. Reinstated as a subspecies of Laothoe populi by Bridges, 1993, Cat. Fam. Gen. Spec. Sphingidae of the World: VIII.12. Resynonymized with the nominotypical subspecies by Vives Moreno, 1994, Cat. sist. sinon. Lepid. Penin. Iberica y Baleares 2: 419. Raised to species status by Danner, Eitschberger & Surholt, 1998, Herbipoliana 4 (1): 109. Resynonymized with Laothoe populi as a subspecies by Kitching & Cadiou, 2000, Hawkmoths of the world: 53. Reinstated as a species by Eitschberger, 2002, Neue ent. Nachr. 53: 154. Resynonymized with Laothoe populi as a subspecies by Kitching and Rougerie et al., 2018, Biodivers. Data J. 6: e22236. Reinstated as a species by Zolotuhin, 2018, Eversmannia 54: 7. Described as a subspecies of Laothoe populi by Eitschberger, Danner & Surholt (1990) (STI 17787), Laothoe populi iberica was raised to species status by Danner, Eitschberger & Surholt (1998) (STI 17413) based mainly on differences in the distal field of cornuti on the vesica and egg chorion morphology. Kitching & Cadiou (2000) (STI 18788) reviewed these characters and concluded that they provided insufficient evidence for species status and reduced iberica once more to a subspecies of Laothoe populi. In reinstating iberica once more as a species, Eitschberger (2002) (STI 17730) simply asserted the revived status. In the absence of any new counterarguments, Kitching & Rougerie et al. (2018) (STI 21830) once more treated iberica as a subspecies of Laothoe populi. Zolotuhin (2018) (STI 21919) reiterated the differences proposed by Danner, Eitschberger & Surholt (1998) (STI 17413) without considering the counterarguments of Kitching & Cadiou (2000) (STI 18788) and also further noted that the shape of the antemedial line on the forewing upperside was different in iberica, straight rather than curved, with only a slight kink near the radial vein. However, examination of the four specimens sampled in BOLD (see below) shows that this character is not consistent. He also noted that the type series of Laothoe populi iberica was mixed, suggesting sympatry of iberica and nominotypical Laothoe populi led to misidentification of the latter as the former. Finally, he noted a DNA barcode divergence of 2.7% between the two taxa, implying as elsewhere in his paper that this level of difference clearly proved the species status of iberica. First, it is certainly true that the type series of Laothoe populi iberica is mixed. The DNA barcodes of the holotype, allotype and two paratypes have been sequenced in BOLD, although those of the holotype and one paratype are short (293bp). Nevertheless, they fall into two different BINs. The holotype and allotype, both from Andalusia in southern Spain, comprise BIN AAM9145, whereas the two paratypes, from Tereul and Segovia in central Spain, fall within a much larger cluster, BIN AAB3599, which includes all Laothoe populi samples from the UK across the Palaearctic to northern Kazakhstan. However, contrary to Zolotuhin's suggestion of sympatry, it is likely that these two clusters are allopatric, with iberica restricted to southern Spain (south of 39°N and east of 6°W) and populi occurring elsewhere on the peninsula. Regarding the DNA barcode divergence, Řezáč (2018) (STI 21910) commented in his study on Rhodoprasina that in that genus “intraspecific divergences are of the order of 4% [and] differences below 2%, unless supported by conspicuous traits in habitus and the structure of the genitalia, cannot be considered significant, even at subspecies level”. This seems to be generally true of many Smerinthini that do not feed as adults and thus, in the absence of such morphological differences, the divergence of 2.7% between iberica and populi indicates subspecies differentiation at best. Taken together, there is thus no justification for treating Laothoe iberica as a species separate from Laothoe populi but rather as a subspecies, Laothoe populi iberica.