title: The sibling species Leptidea juvernica and L. sinapis (Lepidoptera, Pieridae) in the Balkan Peninsula: ecology, genetic structure, and morphological variation.
abstract: The wood white butterfly Leptidea sinapis and its more recently discovered sibling species L. reali and L. juvernica have emerged as a model system for studying the speciation and evolution of cryptic species, as well as their ecological interactions in conditions of sympatry. Leptidea sinapis is widely distributed from Western Europe to Central Asia while the synmorphic L. juvernica and L. reali have allopatric distributions, both occurring in sympatry with L. sinapis and exhibiting an intricate, regionally variable ecological niche separation. Until now, the Balkan Peninsula remained one of the major unknowns in terms of distribution, genetic structure, and ecological preferences of the Leptidea triplet in Europe. We present new molecular and morphological data from a detailed survey of the region. Our DNA analysis suggests that the Balkan populations belong only to L. sinapis and L. juvernica, and that they are not genetically differentiated from other mainland populations. The distribution data reveal that L. sinapis is a widespread habitat generalist, while L. juvernica exhibits a transition from a habitat generalist in the western Balkans to a localised habitat specialist, confined to humid mountain habitats, in the east. The morphometric analysis of male genitalia and a comparison to data from other parts of the species' ranges suggest an interesting mosaic of regional morphological variation that is likely linked to environmental and ecological factors. We also demonstrate the usefulness of the genitalia scaling relations for analysing the morphological variation and discuss the implications for species identification.
authors.affiliation: Department of Physics, University of Ottawa, 150 Louis Pasteur, Ottawa, ON K1N 6N5, Canada. Electronic address: nshtinkov@uottawa.ca.
authors.forename: Nikolay
authors.initials: N
authors.lastname: Shtinkov
authors.affiliation: National Museum of Natural History, 1 Tsar Osvoboditel Blvd, 1000 Sofia, Bulgaria.
authors.forename: Zdravko
authors.initials: Z
authors.lastname: Kolev
authors.affiliation: Institut de Biologia Evolutiva (CSIC-Universitat Pompeu Fabra), Passeig Marítim de la Barceloneta 37, 08003 Barcelona, Spain.
authors.forename: Roger
authors.initials: R
authors.lastname: Vila
authors.affiliation: Institut de Biologia Evolutiva (CSIC-Universitat Pompeu Fabra), Passeig Marítim de la Barceloneta 37, 08003 Barcelona, Spain; Biodiversity Institute of Ontario, University of Guelph, Guelph, ON N1G 2W1, Canada.
authors.forename: Vlad
authors.initials: V
authors.lastname: Dincă
mesh_terms: D000818:Animals; D063368:Balkan Peninsula; D002080:Butterflies / Q000033:anatomy & histology* / Q000145:classification / Q000235:genetics*; D017753:Ecosystem; D005260:Female; D005835:Genitalia / Q000033:anatomy & histology; D008297:Male; D017422:Sequence Analysis, DNA
keywords: Cryptic species; Ecological niche separation; Genital morphology; Leptidea species complex; Speciation