Co-Evolution of <i>Iolana</i> Blues with Their Host Plants and the Higher Phylogeny of Subtribe Scolitantidina (Lepidoptera, Lycaenidae)

Abstract

We investigated the evolutionary relationships between the taxa in the butterfly genus Iolana Bethune-Baker, 1914 and others in the subtribe Scolitantidina using information from nine DNA markers (COI-COII, ND1, ITS2, 28S, CAD, EF-1α, wg, and H3). We show that the genus Iolana originated about 10 mya in Central Asia and gradually expanded to the west to reach Europe about 5 mya. We then compared our inferred phylogeny with that of the Iolana larval host plants in the genus Colutea, reconstructed using three DNA markers (ITS, matK, and rpl32). Although the host plant phylogeny was weakly resolved, the close spatiotemporal correlation between Iolana butterflies and their larval hosts suggests that they may have co-evolved. Based on the molecular results and the morphology of male and female genitalia, we confirm nine species in the genus Iolana, which are distributed in allopatry from Europe and North Africa to Central Asia. We synonymize I. andreasi andreasi Sheljuzhko, 1919 (=I. andreasi khayyami Bernardi, 1964 syn. nov.) and I. iolas wullschlegeli Oberthür, 1914 (=I. iolas protogenes Fruhstorfer, 1917 syn. nov.).

Keywords

• blue butterflies
• Palearctic
• historical biogeography
• comparative phylogenetics
• co-evolution
• co-cladogenesis