Phylogeography of Anterastes Serbicus Species Group (Orthoptera, Tettigoniidae): Phylogroups Correlate With Mountain Belts, but Not With the Morphospecies

Abstract

Ten species of the genus Anterastes Brunner von Wattenwyl (Orthoptera, Tettigoniidae) show insular distribution in mountain meadows of Anatolia and the Balkans. Current understanding of the taxonomy and species relationships within the genus is based on morphological characters. However, the extent to which morphological characters are phylogenetically informative, when used to define taxonomic groups or to elucidate detailed evolutionary relationships within Anterastes, is in need of further examination. Moreover, because little is known about the historical biogeography and diversification factors in members of this genus, additional datasets are necessary to test the robustness of species, relationship hypotheses and associated biogeographic patterns, Here we specifically examined, using 16S rDNA sequences, the evolutionary relationships and species boundaries of three closely related species of Anterastes (i.e., the A. serbicus group, comprising A. serbicus, A. burri and A. antitauricus). Additionally A. tolunayi, a species not in the A. serbicus group, but morphologically very similar to members of the group, was included in the molecular analysis to locate the species of the A. serbicus complex within a phylogenetic frame. Hence, the phylogenetic relationships and taxonomic interpretation of the species complex appear more intricate than previously hypothesized, The current molecular data do not allow us to identify A. serbicus, A. burri and A. antitauricus as distinct phylogenetic species, but rather suggest that these morphospecies are themselves a complex of cryptic taxa. Despite the incongruencies among the phylogenetic trees and nonmonophyly of each the three morphospecies, the median joining network resulted in haplotype grouping consisting of four clusters that are definable by geography. Thus, based on the congruency between geography and gene clusters, and the molecular clock estimate, it can be interpreted that 1) a strong correlation between the radiation of the group and the topography of their ranges may exist, 2) the radiation of the group dates back to Late Pliocene or Early Pleistocene and 3) there is a break between the Anatolian and the European lineages, in respect to range change of cold-preferring forms, dating back prior to the last four glacial periods.