Mountainous genus <i><scp>A</scp>nterastes</i> (<scp>O</scp>rthoptera, <scp>T</scp>ettigoniidae): autochthonous survival across several glacial ages via vertical range shifts

Abstract

Although the high‐latitude range margins in E urope and N orth A merica are intensively studied, attention is gradually turned towards the taxa/populations inhabiting glacial refugia. Here, we evaluate the genealogical history of the cold‐adapted A natolio‐ B alkan genus A nterastes especially to test the possible effects of intrarefugial vertical range shifts during climatic oscillations of the Q uaternary. Using concatenated data from sequences of COI +16 S and ITS 1–5.8 S – ITS 2, intrageneric relationships and the time of speciation events were estimated. Thirteen different demographic analyses were performed using a data set produced from sequences of 16 S . Different phylogenetic analyses recovered similar lineages with high resolution. The molecular chronogram estimated speciation events in a period ranging from 5.60 to 1.22 Myr. Demographic analyses applied to 13 populations and five lineages suggested constant population size. Genetic diversity is significantly reduced in a few populations, while not in others. Fixation indices suggested extremely diverged populations. In the light of these data, the following main conclusions were raised: (i) although glacial refugia are the biodiversity hotspots, species level radiation of the cold‐adapted lineages is mainly prior to the M id‐ P leistocene transition; (ii) heterogeneous topography provides refugial habitats and allows populations to survive through vertical range shifts during climatic fluctuations; (iii) prolonged isolation of refugial populations do not always result in reduced intrapopulation diversity, but in high level of genetic differentiation; (iv) the cold‐adapted lineages with low dispersal ability might have not colonised the area out of Anatolian refugium during interglacial periods; and (v) populations of invertebrates may have restricted ranges, but this does not mean that they have small effective population size.