Contrasting genetic structure in cuckoo and predatory Maculinea butterflies

Abstract

In Europe, both Maculinea alcon and M. teleius frequently co-occur inhabiting humid meadows. Although their parasitic life cycle is similar, ecological differences have been demonstrated between them: (i) spatial distribution of their eggs is different, and (ii) M. alcon is a cuckoo species, while M. teleius is predatory. The aim of the present study is to identify the genetic consequences of the ecological differences between these two butterfly species. To do so, we studied the genetic structure in samples from 9 M. alcon and 16 M. teleius sites obtained from the Carpathian Basin using 16 polymorphic enzyme markers. Both species exhibited relatively low enzyme polymorphism compared to other lycaenid species. Nevertheless, all measures of variation were significantly higher in M. teleius than in M. alcon. Genetic differentiation, however, was generally higher among M. alcon populations as compared to M. teleius. Moreover, the results of Bayesian clustering indicated a clear regional pattern with three well-defined cluster regions in M. alcon. In contrast, the regional pattern was less evident in M. teleius where we found three comparatively less distinct cluster regions. Putatively adaptive genetic differences were detected among cluster regions exploiting different host ants in M. alcon, while they were less evident in M. teleius. These results conform to our predictions on the differences between the utilization of their host ants. Since the pattern of genetic differentiation is different in the two Maculinea species, conservation strategies need also to differ in their cases.

Surprising diversity in the Pannonian populations of Marsh Fritillary (Euphydryas aurinia, Lepidoptera: Nymphalidae): Morphometric and molecular aspects

“…Certain results of the enzyme studies (the allele frequency distribution of the clusters and the N m values) suggested that this relatively higher level of differentiation between the eastern and western populations is mostly due to the presence of specific alleles in Transylvania. We have observed a somewhat similar pattern of geographic differentiation in Phengaris ( Maculinea ) nausithous with significantly higher genetic diversity in the Transylvanian populations (Hollós et al., ; Pecsenye et al., ). Junker et al.…”

“…Regardless of their taxonomic position, they often display a moderate level of genetic diversity within the populations coupled with a considerable differentiation among them with more or less clear geographic patterns, for example, Phengaris spp. (Hollós et al., ; Pecsenye et al., ; Sielezniew et al., ), Erebia medusa (Schmitt & Seitz, ), and also Euphydryas aurinia (Junker et al., ; Korb, Bolshakov, Fric, & Bartonova, ).…”

“…Historic events are more clearly reflected in sequence variation of mitochondrial DNA (mtDNA) or standard nuclear genes as they indicate the origin of the populations going back to the glacial periods and their colonization routes to the present habitats (e.g., Hewitt, ; Seddon, Santucci, Reeve, & Hewitt, ; Stauffer, Lakatos, & Hewitt, ; Taberlet, Fumagalli, Wust‐Saucy, & Cosson, ). At the same time, different nuclear marker loci (e.g., allozymes or microsatellites) usually show higher variation than standard genes, and thus they provide finer resolution to study the effect of recent past processes such as drift or selection (e.g., Besold, Schmitt, Tammaru, & Cassel‐Lundhagen, ; Karl, Schmitt, & Fischer, ; Pecsenye, Bereczki, Juhász, Tartally, & Varga, ). Finally, phenotypic variation (e.g., morphometric variation) mirrors contemporary evolutionary effects and is strongly associated with local adaptation (e.g., Collin & Fumagalli, ; Norberg & Leimar, ; Stöcklin, Kuss, & Pluess, ).…”