World travellers: phylogeny and biogeography of the butterfly genus Leptotes (Lepidoptera: Lycaenidae)
Abstrakt
Leptotina butterflies (Lycaenidae, Polyommatiinae) are found mostly in tropical and subtropical areas around the globe, marginally penetrating into temperate regions. Here, we investigated phylogenetic and biogeographical relationships of most representatives of the subtribe, using both likelihood and Bayesian approaches.
We also estimated the timing of their diversification. And lastly, we studied phylogeographic patterns of the most widespread species, Leptotes pirithous.
DNA sequences from two mitochondrial (COI, COII) and two nuclear genes (wingless, Ef1 alpha) were analysed for 13 species of the genus Leptotes Scudder and one species of the genus Cyclyrius Butler. Both genera together form a monophyletic clade, and Cyclyrius is rooted deep inside Leptotes.
Therefore, we designate Cyclyrius to be a junior synonym of Leptotes. According to our study, the genus Leptotes originated between the late Eocene and early Oligocene (35-31 Ma).
During the Miocene it dispersed to the rest of the southern hemisphere, with further speciation events within the Indo-Australian region, and separate radiations in the Americas and the Afrotropics. Leptotes webbianus from the Canary Islands turned out to be sister to the American clade from which it split c. 12 Ma.
Leptotes pirithous originated in Madagascar c. 4 Ma and invaded the whole of Africa and southern Europe, including numerous surrounding islands. Populations of L. pirithous from Mauritius and Madagascar turned out to represent a distinct species (Leptotes durrelli sp.n.) and the same applies to the Australasian populations of Leptotes plinius (Leptotes lybas stat. rev.).