Allozyme variation in Polyommatus coridon (Lepidoptera: Lycaenidae): identification of ice‐age refugia and reconstruction of post‐glacial expansion

Abstract

Aim The effects of glacial disjunctions on intraspecific differentiations are in the focus of phylogeographical studies. Several studies investigate the consequences of post‐glacial expansions from glacial refugia on the composition within major genetic lineages. Location and methods We analysed the geographical pattern of allozyme variation of twenty loci of Polyommatus coridon (Poda, 1761) (Lepidoptera: Lycaenidae) from thirty‐six localities spread throughout large regions of its European range. A total of 1566 individuals were analysed. Results We obtained a significant genetic differentiation (FST 0.060 ± 0.007). Further analyses showed a division into two major genetic lineages with a mean genetic distance (Nei, 1978) of 0.041 (± 0.010 SD). Applying an AMOVA, more than three quarters of the variance between populations was between these lineages and less than one quarter within these lineages. Both genetic lineages showed a significant decline in the number of alleles from southern to northern populations. Furthermore, we found a contact zone of these two major genetic lineages in eastern Central Europe extending throughout north‐eastern Germany, then following the mountain regions along the Czech‐German border and passing through the eastern Alps in a north–south direction. Main conclusions We assume that this differentiation evolved during the last ice‐age as a result of isolation in the Adriato‐ and the Ponto‐Mediterranean region. The loss of genetic diversity from the south to the north within both lineages reflects the decline of diversity during the post‐glacial expansion.

Evidence for a residual postglacial founder effect in a highly dispersive freshwater invertebrate

“…Discussion-The significantly higher levels of genetic diversity in C. mucedo collected from central/southern Europe versus those from northern Europe are consistent with numerous previous studies that have found an inverse relationship between genetic diversity and distance from glacial refugia (e.g., Armbruster et al 1998;Hewitt 1999;Schmitt and Seitz 2001). This may be attributed to leading edge colonization, in which individuals from the northerly limits of the refugia are the first to colonize recently unglaciated regions, and later immigrants cannot easily invade these established populations.…”

Postglacial colonisation of western Central Europe by Polyommatus coridon (Poda 1761) (Lepidoptera: Lycaenidae): evidence from population genetics

“…In a previous study, we showed that P. coridon colonised our study area from an ice-age refugium in Italy (Schmitt and Seitz, 2001a). Now, we present the analysis of the genetic effects of the postglacial expansion process and their consequences for the identification of possible expansion corridors.…”

“…Therefore, the results for this enzyme were excluded from all calculations of genetic Table 1. The northern limit of distribution (Tolman and Lewington, 1998, modified) is indicated by a broken line, the border between the Adriato-and the Ponto-Mediterranean genetic lineages conforming phenotypic differentiation (Schmitt and Seitz, 2001a) is indicated by a dotted line and the distribution range of the Adriato-Mediterranean lineage by a shaded area.…”

Refugial Pattern of Bromus Erectus in Central Europe Based on Issr Fingerprinting

“…Genetic analyses of the species on the European scale revealed two glacial differentiation centers, western and eastern (Schmitt and Seitz, 2001). This bi-division is best explained by a long period of disjunction in two ice-age refugia, AdriaticMediterranean and Pontic-Mediterranean.…”