Coenonympha Hero Research Articles

Population decline at distribution margins: Assessing extinction risk in the last glacial relictual but still functional metapopulation of a European butterfly

AbstractAimTo determine the interplay between climate and land use changes in driving population dynamics in a butterfly species, Coenonympha hero, at the southern limit of its distribution.LocationFrench Jura massif and Europe.MethodsWe analysed patterns of genetic diversity distribution at 817 loci in 136 butterflies from 31 sites using NGS to infer the genetic structure and population size changes over time, using two methods of demographic inference (SNP frequency spectrum analyses and coalescent ABC inferences). We then characterized the climate and land use descriptors of C. hero geographic distribution using species distribution modelling (SDM) and ordination method and compared demographic changes to changes in climatically suitable areas.ResultsCoenonympha hero persists in the Jura massif as three core populations that share a common history of decline in two steps: an old decline and a more recent decline that resulted in population fragmentation, the southernmost sites being the most threatened (lowest genetic diversity). Climate change during the Würm glaciation is presumably the main factor explaining the first demographic decline. The second decline started 2000 years ago possibly under increased human pressure as suggested by recent extinctions in several sites nowadays characterized by urban and agricultural surfaces. Both climate and land use variables are important descriptors of C. hero distribution, as SDM predictions were improved by adding aridity index, altitude and land use to bioclimatic predictors. Its habitats include forests in north‐eastern Europe and grasslands in the Jura massif.Main conclusionsUsing SDM and genetic demographic inferences, we identified a persistent glacial refuge for the species in Europe. We show that although this relictual population has declined and fragmented under the combined effects of climate warming and anthropization, the metapopulation is still functional but requires particular conservation attention to maintain its connectivity, and to favour the local persistence of this highly endangered butterfly species.

Phenotypic variation of the scarce heath Coenonympha hero (L.) (Lepidoptera, Satyridae) from the central part of its range

Variation of the fore and hind wing lengths and the diameters of wing eyespots in two subspecies of Coenonympha hero (L.) from the central part of the species range was analyzed. Clinal variation was revealed, manifested in a gradual increase of the wing size and eyespot diameters from west to east in the Urals. Both in C. h. hero in the Urals and in C. h. perseis in Siberia, the northern peripheral populations had a specific wing pattern with eyespots smaller than in more southern parts of the corresponding ranges. In most cases, such climatic factors as the mean annual air temperature, precipitation, duration of the frost-free period, and humidity were shown to affect significantly the variation of morphological traits of C. hero. Chrono-geographical analysis of variation showed that in some cases the differences between the samples collected in the same locality in different years were comparable to or greater than geographic variation within the subspecies range. Thus, the population as a whole is influenced by climatic factors and weather conditions in a particular part of the range during a particular season; C. hero may therefore be a suitable object for monitoring the impact of environmental changes on insects.

Host associations of Coenonympha hero (Lepidoptera: Nymphalidae) in northern Europe: microhabitat rather than plant species

Understanding ecological requirements of endangered species is a primary precondition of successful conservation practice. Regrettably, we know surprisingly little about the life history of numerous threatened insects, and about their use of larval host plants in particular. The brown butterflies (Nymphalidae: Satyrinae) have traditionally been considered polyphagous on grasses and indiscriminatory in their oviposition behavior. However, detailed studies on several species have revealed local specialization in host plant use as well as the decisive role of microlimatic conditions as determinants of habitat quality. The present study addresses host plant relationships in the endangered brown butterfly Coenonympha hero (L.) at the northern limit of its European distribution. We combine laboratory-based host preference and performance tests with an analysis of microhabitat use by adult butterflies in the field. Both lines of evidence suggest that C. hero is polyphagous enough not to be associated with one particular host species. Oviposition choices of C. hero are not driven by host plant species but rather by structural characteristics of the substrate. The preferred rigid needle-like structures may serve as cues of ‘transparent’ vegetation which allows the larvae to benefit from sunlight reaching the lower strata of the tuft. Our results suggest that conservation efforts should prioritize microclimatic parameters, rather than the presence of any particular host plant species, as decisive determinants of habitat quality in C. hero.

Butterflies and skippers (Lepidoptera, Diurna) from the Republic of Mordovia

According to the data obtained, the Mordovian fauna of diurnal lepidopterans comprises 75 species, including Hesperiidae (7 species), Papilionidae (5), Pieridae (10), Satyridae (10), Nymphalidae (27), and Lycaenidae (16). Based on the quantitative assessments, the species were characterized as rare (1–5 ind. in the collection), scarce (6–30), common (31–170), and abundant (171–940). Species with temperate (52 species or 69.3%) and subboreal (12 species or 16.0%) ranges predominated in the latitudinal distribution pattern. The total and background species diversity of the Diurna was the highest in the forests (63 species) and meadows (52), and the lowest on the steppe slopes (6). Among the species revealed, 14 were rare: Iphiclides podalirius, Zerynthia polyxena, Parnassius apollo, Driopa mnemosyne, Colias erate, Coenonympha hero, Neptis sappho, Apatura iris, Limenitis populi, Nymphalis antiopa, Fixsenia pruni, Lycaena helle, Cupido minimus, and Maculinea arion.

Current Perspectives on Percutaneous Vertebroplasty: Current Evidence/Controversies, Patient Selection and Assessment, and Technique and Complications

Osteoporotic-associated vertebral compression fractures are a major public health concern, dwarfing even hip fractures in incidence in the United States. These fractures carry a significant morbidity and mortality burden and also represent a major growing source of consumption of scarce heath resources. Percutaneous vertebroplasty remains a commonly used and safe technique for the symptomatic treatment of vertebral compression fractures, both osteoporotic- and neoplastic-induced. By carefully selecting appropriate patients who are referred promptly, vertebroplasty can provide significant and durable pain relief over traditional conservative therapy. Recent controversies surrounding the evidence for vertebroplasty in osteoporotic-associated vertebral compression fractures are reviewed. A comprehensive step-by-step practical guide to performing vertebroplasty is then described. A brief description of patient selection, workup, as well as complications is also provided.

Effects of patch characteristics and isolation on relative abundance of the scarce heath butterfly Coenonympha hero (Nymphalidae)

The scarce heath (Coenonympha hero) is an internationally threatened butterfly in Western Europe, where it occurs primarily on hay fields and abandoned arable land in a small-scale agricultural landscape of south-central Scandinavia. Due to afforestation, this habitat is becoming increasingly fragmented in Sweden, and it can be expected that the scarce heath will decline abruptly when threshold conditions for metapopulation persistence are no longer met. We used stepwise polychotomous logistic regression to compare habitat characteristics and isolation measures for patches that harbour large, small or no populations, respectively, in an area of south-western Sweden. We found that patch area, distance to the nearest large population and amount of Galium spp. explained a significant part of the variation in relative abundance among patches. Distance to nearest large population resulted in a better model to predict occupancy than both distance to the nearest inhabited patch and connectivity, which suggests that primarily large populations act as sources for small satellite populations. Today, sites of three of the eight larger populations in the study area have been planted with spruce or pine and will disappear within 20 years. We argue that the disappearance of these patches may very well lead to rapid extinction of the whole metapopulation system.

Limited dispersal by the rare scarce heath butterfly—potential consequences for population persistence

Dispersal between habitat patches may be important for the long-term persistence of populations. We conducted a mark–release–recapture study and analysed the dispersal pattern in the scarce heath butterfly inhabiting a network of suitable habitat patches using stepwise logistic regression (SLR) and the Virtual Migration (VM) model. We also analysed the influence of different types of matrices. We found that the majority of the recaptured butterflies remained within the patch where they were originally caught. However, dispersal between patches did occur and both the SLR analysis and the VM model indicated that the migration pattern was significantly associated with patch area and its level of isolation. The SLR model also showed that there was a positive association between immigration rate and tree density, supporting earlier observations that this species prefers semi-open habitat. We discuss the use of SLR versus the VM model to analyse recapture data in dispersal studies. This system is not at equilibrium, as a number of the most important patches in the network are continuously being lost due to afforestation and a number of populations are facing deterministic extinction. This increases the risk of a chain reaction of local extinctions, which may cause a collapse of the whole system.

Allozyme variability in central, peripheral and isolated populations of the scarce heath (Coenonympha hero: Lepidoptera, Nymphalidae): Implications for conservation

Genetic drift tends to lower geneticvariability in peripheral and isolatedpopulations. These populations also tend todiverge from more central populations if thedegree of isolation is high enough. Theseprocesses could have opposite effects on thevalue of the respective populations in thespecies conservation context. On the basis ofallozyme polymorphism data, we compare geneticvariability and differentiation between core,peripheral and isolated populations of thescarce heath, a butterfly endangered inNorthern and Central Europe. Genetic variationwas lowest in populations that were bothperipheral and isolated(P = 16.5%, Hobs = 0.017),and highest in the central populations(P = 35%,Hobs = 0.052). However, overall variability waslow also in the core area compared to that ofclosely related butterfly species. Theperipheral region was more differentiated fromthe other regions than the isolated region(FPC = 0.118, FPI = 0.257,FIC = 0.068). This study indicated thatisolation in combination with marginality havecaused an erosion of the gene pool. Theobserved patterns may be caused both by thecontemporary population structure of thespecies, as well as by the colonisationhistory. Both genetic and ecological evidencesuggests that the species is likely to followthe stepping-stone model of dispersal.

Characterization of microsatellite loci inCoenonympha hero(Lepidoptera: Nymphalidae)

AbstractMicrosatellite markers are suitable tools for studying dispersal pattern among local populations. I report on the characterization of seven polymorphic microsatellite loci in the scarce heath butterfly (Coenonympha hero), from one unenriched and one enriched genomic library. Number of alleles ranged from two to 20 when 108 individuals from seven populations were screened.HOranged from 0.140 to 0.889. Primers were also tested on three other butterfly species. Amplification was successful for all loci inErebia triaria, while only one gave products inMaculinea alconandMaculinea rebeli.To my knowledge, these are the first microsatellite markers published in theNymphalidaesubfamilySatyrinae.

Effects of Population Size and Food Stress on Fitness‐Related Characters in the Scarce Heath, a Rare Butterfly in Western Europe

Abstract: Knowledge about the effects of inbreeding in natural populations is scarce, especially in invertebrates. We analyzed to what extent fitness‐related traits in the scarce heath ( Coenonympha hero), a butterfly, are affected by population size and isolation and whether differences in food quality influence these effects. We categorized nine populations as either large or small and isolated. Full‐sib groups of offspring from 27 females were followed under seminatural conditions. Because of increased zygote mortality, egg hatchability was significantly lower in the small and isolated populations than in the large ones. Population category had no effect on larval weight under optimal conditions, but weight was significantly lower in the small‐isolated category with low food quality. The effects of inbreeding can thus be hidden when conditions are benign but can appear under stress. Survival also differed significantly between population categories, and larval developmental time tended to be longer in the small‐isolated category, irrespective of food conditions. We suggest that the differences in fitness between offspring from large and small isolated populations are at least partly due to inbreeding. This adds a further threat to a species that is already suffering from decreasing population sizes and increasing isolation among populations.