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The grape berry moth Eupoecilia ambiguella (Lepidoptera: Tortricidae) is causing significant damage to grape berries, however, little is known on population genetics of this lepidopteran pest insect, hindered so far by the lack of suitable molecular markers. Here we report on the development of ten microsatellite markers of which six were used to characterise 21 E. ambiguella populations obtained from two viticultural regions in Germany and Italy. Moths were sampled during two subsequent generations (flights) in the same vineyard as well as in vineyards surrounded by different landscape types. German and Italian populations were genetically differentiated and a significant isolation by distance was evident. No significant divergence was observed among the populations from first or second flight moths, however, inbreeding was higher in first than in second flight populations. Moreover, inbreeding was influenced by habitat composition and complexity of landscape around vineyards, being positively associated with the percentage of area covered by grapevine. Population genetics of E. ambiguella could thus be affected by the presence of alternative host plants in viticultural landscapes, which is important in the light of both insecticide resistance management and sustainable pest management. [ABSTRACT FROM AUTHOR]

The invasion of the Western Hemisphere native fall armyworm (Spodoptera frugiperda; J. E. Smith) (Lepidoptera: Noctuidae) into the Eastern Hemisphere has been notable for the rapidity and geographical breadth of new detections. In the year following the first discovery in western sub-Saharan Africa in 2016, infestations have been documented in most sub-Saharan maize growing regions and has now expanded beyond Africa with populations recently reported in India. These observations could indicate a remarkable capacity for rapid establishment and long-distance dissemination. However, while fall armyworm does exhibit extended migration in North America where it annually traverses thousands of kilometers, this behavior is known to be dependent on highly favorable wind patterns and so can’t be assumed to occur in all locations. An alternative possibility is that the species has long been present in Africa, and perhaps the rest of the hemisphere, but was undetected until the enhanced monitoring that resulted after its initial discovery. Determining whether the fall armyworm in the Eastern Hemisphere is newly arrived or long pre-existing is important for assessing the risks of significant economic impacts, as the former indicates a change in pest composition while the latter does not. This study examined this issue by comparing collections from two geographically distant locations, South Africa and India. Sequence comparisons were used to quantify differences between the South Africa and India collections, assess the likelihood of their sharing a common source population, and their possible relationship with previously characterized fall armyworm from other regions of Africa. The results indicate genetic homogeneity between the South African and Indian fall armyworm populations tested and substantial similarities between these and collections from eastern Africa. The implications of these findings on fall armyworm population behavior and composition are discussed. [ABSTRACT FROM AUTHOR]

Population genetic structuring is common among herbivorous insects and frequently is associated with divergent host plants, such as crops and their wild relatives. Previous studies showed population genetic structuring in corn leafhopper Dalbulus maidis in Mexico, such that the species consists of two sympatric, host plant‐associated populations: an abundant and widespread "pestiferous" population on maize (Zea mays mays), and a small and localized "wild" population on perennial teosinte (Zea diploperennis), a maize wild relative with a limited distribution. This study addressed whether assortative mating and immigrant inviability mediate genetic structuring of corn leafhopper by comparing the mating and reproductive successes of pestiferous and wild females that colonize their nonassociated host plants against the successes of females colonizing their associated host plants. Assortative mating was assessed by comparing mating frequencies and premating and mating times among females of each population on each host plant; immigrant inviability was assessed by comparing, across two generations, the fecundity, survival, development time, sex ratio, and population growth rate among leafhopper populations and host plants. Our results showed that on maize, and compared to resident, pestiferous females, wild females were more likely to mate, and greater proportions of their offspring survived to adult stage and were daughters; consequently, the per‐generation population growth rate on maize was greater for immigrant, wild leafhoppers compared to resident, pestiferous leafhoppers. Our results suggested that wild leafhoppers emigrating to maize have a fitness advantage over resident, pestiferous leafhoppers, while immigrant pestiferous and resident wild leafhoppers on teosinte have similar fitnesses. [ABSTRACT FROM AUTHOR]

The genus Neotrogla (Psocodea: Prinoglarididae) comprises four named species from Brazil. Females of this cave‐dwelling insect are characterized by a conspicuous penis‐like intromittent organ, termed a gynosome, which is inserted into the vagina‐like male genitalia during copulation. Another evolutionarily novel structure, the spermathecal plate, enables a female to simultaneously store two freshly deposited spermatophores (consisting of sperm and possibly nutritious substances) in her sperm storage organ (spermatheca). It is unknown whether the two spermatophores are derived from two different males. To investigate the mating ecology and population genetic structures of these insects with sex‐reversed genitalia, 16 novel highly polymorphic microsatellite loci were isolated and characterized based on ~2,275 Mbp genomic sequences from an undescribed Neotrogla species. Our first screening detected 99,888 candidate loci. Similar to other hemipteroid insects studied thus far, AAT motif microsatellites were conspicuously dominant. We further screened 99 sequences, for which 50 pairs of polymerase chain reaction primers were successfully designed. Sixteen of these primers successfully amplified products of the expected size in the 11 Neotrogla sp. individuals collected from two caves. The number of alleles per loci varied from two to nine, with no significant deviation from the Hardy–Weinberg equilibrium in either population. Although the caves sampled were only approximately 1 km apart, significant genetic differentiation was detected between the two populations. In total, 13, 12, 13 and 11 loci were cross‐amplified in N. aurora, N. brasiliensis, N. curvata and N. truncata, respectively, indicating the applicability of these microsatellite loci for metapopulation genetic studies in multiple Neotrogla species. Females of Brazilian cave‐dwelling insect genus Neotrogla (Psocodea: Prinoglarididae) are characterized by a conspicuous penis‐like intromittent organ. Sixteen novel highly polymorphic microsatellite loci were isolated and characterized based on ~2,275 Mbp genomic sequences from an undescribed Neotrogla species. [ABSTRACT FROM AUTHOR]

Understanding the mechanisms that enforce, maintain or reverse the process of speciation is an important challenge in evolutionary biology. This study investigates the patterns of divergence and discusses the processes that form and maintain divergent lineages of the tsetse fly Glossina fuscipes fuscipes in Uganda. We sampled 251 flies from 18 sites spanning known genetic lineages and the four admixture zones between them. We apply population genomics, hybrid zone and approximate Bayesian computation to the analysis of three types of genetic markers: 55,267 double‐digest restriction site‐associated DNA (ddRAD) SNPs to assess genome‐wide admixture, 16 microsatellites to provide continuity with published data and accurate biogeographic modelling, and a 491‐bp fragment of mitochondrial cytochrome oxidase I and II to infer maternal inheritance patterns. Admixture zones correspond with regions impacted by the reorganization of Uganda's river networks that occurred during the formation of the West African Rift system over the last several hundred thousand years. Because tsetse fly population distributions are defined by rivers, admixture zones likely represent both old and new regions of secondary contact. Our results indicate that older hybrid zones contain mostly parental types, while younger zones contain variable hybrid types resulting from multiple generations of interbreeding. These findings suggest that reproductive barriers are nearly complete in the older admixture zones, while nearly absent in the younger admixture zones. Findings are consistent with predictions of hybrid zone theory: Populations in zones of secondary contact transition rapidly from early to late stages of speciation or collapse all together. [ABSTRACT FROM AUTHOR]

Leucinodes orbonalis is a destructive pest found throughout eggplant cultivating fields of Tamil Nadu, India. The genetic diversity and its population structure were investigated in this pest using mitochondrial cytochrome c oxidase subunit I (COI) gene sequences from 20 populations of L. orbonalis collected from various agro-climatic conditions. The study indicated almost no genetic diversity among various populations. The COI nucleotide sequence based haplotype analysis also revealed no significant genetic variation among various populations. However, haplotype network analysis with three clades was nearly matching with the structure of phylogenetic analysis that showed geographical separations induced distribution of some genetic variation. The PCA and nMDS Shephard's plot analyses were also illustrated that the populations sampled were nearly matched with phylogenetic tree and haplotype network. This study on phylogeographical structure using the mitochondrial COI sequence diversity of L. orbonalis therefore suggested presence of few genetically distinct populations due to some specific habitat requirements. [ABSTRACT FROM AUTHOR]

Bactrocera carambolae Drew and Hancock and Bactrocera dorsalis (Hendel) (Diptera: Tephritidae) are important pests of many fruits. These flies have been spread across the world through global travel and trade, and new areas are at risk of invasion. Whenever new invasive populations are discovered, quick and accurate identification is needed to mitigate the damage they can cause. Determining invasive pathways can prevent further spread of pests as well as subsequent reinvasions through the same pathway. Molecular markers can be used for both species identification and pathway analysis. We analyzed 1,601 individuals from 19 populations using 765 base pairs of the mitochondrial cytochrome oxidase I (COI) gene to infer the haplotype diversity and population structure within these flies from across their native and invasive ranges. We analyzed these samples by either grouping by species or geographic populations due to the genetic similarity in the mitochondrial genome. We found no genetic structure between B. dorsalis and B. carambolae and our findings suggest recent and most likely ongoing, genetic exchange between these two species in the wild. Hyper-diverse mitochondrial genetic diversity in the native range suggests large population sizes and relatively high mutation rates. Only 52% of the haplotypes found in the trap captures from California are shared with haplotypes from flies found in our global survey, indicating significant genetic diversity in the native range that is missing from our samples. However, these results provide a foundation for the accurate determination of the provenance of invasive populations around the world. [ABSTRACT FROM AUTHOR]

When predators commonly overexploit local prey populations, dispersal drives the dynamics in local patches, which together form a metapopulation. Two extremes in a continuum of dispersal strategies are distinguished: the "Killer" strategy, where predators only start dispersing when all prey are eliminated, and the "Milker" strategy, in which predator dispersal occurs irrespective of prey availability. Theory shows that the Milker strategy is not evolutionarily stable if local populations are well connected by dispersal. Using strains of the predatory mite Phytoseiulus persimilis, collected from 11 native populations from coastal areas in Turkey and Sicily, we investigated whether these two strategies occur in nature. In small wind tunnels, we measured dispersal rates and population dynamics of all populations in a system consisting of detached rose leaves, spider mites (Tetranychus urticae) as prey, and P. persimilis. We found significant variation in the exploitation and dispersal strategies among predator populations, but none of the collected strains showed the extreme Killer or Milker strategy. The results suggest that there is genetic variation for prey exploitation and dispersal strategies. Thus, different dispersal strategies in the Milker–Killer continuum may be selected for under natural conditions. This may affect the predator–prey dynamics in local populations and is likely to determine persistence of predator–prey systems at the metapopulation level. When predators commonly overexploit local prey populations, dispersal drives the dynamics in local patches, which together form a metapopulation. We present a comprehensive survey of predator dispersal strategies using strains of Phytoseiulus persimilis, collected from 11 native populations from coastal areas in Turkey and Sicily. We found significant variation in the exploitation and dispersal strategies among predator populations, suggesting that there is genetic variation for prey exploitation and dispersal strategies. [ABSTRACT FROM AUTHOR]

The range of thermal tolerance is one of the main factors influencing the geographic distribution of species. Climate change projections predict increases in average and extreme temperatures over the coming decades; hence, the ability of living beings to resist these changes will depend on physiological and adaptive responses. On an evolutionary scale, changes will occur as the result of selective pressures on individual heritable differences. In this work, we studied the genetic basis of tolerance to high temperatures in the fly Drosophila melanogaster and whether this species presents sufficient genetic variability to allow expansion of its upper thermo‐tolerance limit. To do so, we used adult flies derived from a natural population belonging to the Drosophila Genetic Reference Panel, for which genomic sequencing data are available. We characterized the phenotypic variation of the upper thermal limit in 34 lines by measuring knockdown temperature (i.e., critical thermal maximum [CTmax]) by exposing flies to a ramp of increasing temperature (0.25°C/min). Fourteen percent of the variation in CTmax is explained by the genetic variation across lines, without a significant sexual dimorphism. Through a genomewide association study, 12 single nucleotide polymorphisms associated with the CTmax were identified. In most of these SNPs, the less frequent allele increased the upper thermal limit suggesting that this population harbors raw genetic variation capable of expanding its heat tolerance. This potential upper thermal tolerance increase has implications under the global warming scenario. Past climatic records show a very low incidence of days above CTmax (10 days over 25 years); however, future climate scenarios predict 243 days with extreme high temperature above CTmax from 2045 to 2070. Thus, in the context of the future climate warming, rising temperatures might drive the evolution of heat tolerance in this population by increasing the frequency of the alleles associated with higher CTmax. We measured critical thermal maxima (CTmax) in a subset of lines of the Drosophila Genetic Reference Panel with a new activity‐sensing device and performed a genomewide association study (GWAS). Through this analysis, we obtained 12 significant SNPs along the genome that are associated with CTmax. In most of these SNPs, the minor alleles increased the upper thermal limit suggesting that this natural population harbors raw genetic variation for expanding its heat tolerance. [ABSTRACT FROM AUTHOR]

Abstract: The habitat template concept applied to a freshwater system indicates that lotic species, or those which occupy permanent habitats along stream courses, are less dispersive than lentic species, or those that occur in more ephemeral aquatic habitats. Thus, populations of lotic species will be more structured than those of lentic species. Stream courses include both flowing water and small, stagnant microhabitats that can provide refuge when streams are low. Many species occur in these microhabitats but remain poorly studied. Here, we present population genetic data for one such species, the tropical diving beetle Exocelina manokwariensis (Dytiscidae), sampled from six localities along a ~300 km transect across the Birds Head Peninsula of New Guinea. Molecular data from both mitochondrial (CO1 sequences) and nuclear (ddRAD loci) regions document fine‐scale population structure across populations that are ~45 km apart. Our results are concordant with previous phylogenetic and macroecological studies that applied the habitat template concept to aquatic systems. This study also illustrates that these diverse but mostly overlooked microhabitats are promising study systems in freshwater ecology and evolutionary biology. With the advent of next‐generation sequencing, fine‐scale population genomic studies are feasible for small nonmodel organisms to help illuminate the effect of habitat stability on species’ natural history, population structure and geographic distribution. [ABSTRACT FROM AUTHOR]

The Aedes aegypti mosquito is a primary vector of several serious arboviruses throughout the world and is therefore of great concern to many public health organizations. With vector control methodology pivoting towards rearing and releasing large numbers of genetically modified, sterilized, or Wolbachia-infected male mosquitoes to control vector populations, economical surveillance methods for release tracking becomes increasingly necessary. Previous work has identified that male Ae. aegypti are attracted to female wingbeat frequencies and can be captured through artificial playback of these frequencies, but the tested systems are cost-prohibitive for wide-scale monitoring. Thus, we have developed a simple, low-cost, battery-powered, microcontroller-based sound lure which mimics the wingbeat frequency of female Ae. aegypti, thereby attracting males. We then tested the efficacy of this lure in combination with a passive (non-powered) gravid Aedes trap (GAT) against the current gold-standard, the Biogents Sentinel (BGS) trap, which requires main power (household power) and costs several times what the GAT does. Capture rates of male Ae. aegypti in sound-baited GATs (Sound-GATs) in these field tests were comparable to that of the BGS with no inhibitory effects of sound playback on female capture. We conclude that the Sound-GAT is an effective replacement of the costly BGS for surveillance of male Ae. aegypti mosquitoes, particularly in the developing countries where funding is limited, and has the potential to be adapted to target males of other medically important species. [ABSTRACT FROM AUTHOR]

1. Many important insect pests undertake seasonal migrations at continental scales in response to changes in resource quality and availability. The frequency and timing of these events could be influenced by the impact of climate change on the suitability of the different sites exploited throughout the year, yet, in many cases, little is known about the origin of seasonal populations, as tracking insect movements is extremely challenging due to their small body size. 2. The use of stable isotope measurements in insect tissues combined with the development of tissue‐specific ‘isoscapes’ of modelled geographic isotope patterns presents a potentially valuable but rarely used approach for obtaining such information on important pest species. In this paper it is illustrated how stable hydrogen isotope analyses (δ2H) in wing chitin of the true armyworm (Mythimna (Psuedaletia) unipuncta Haworth), a seasonal migrant, clearly delineated between 2016 spring immigrants and later locally produced moths in southern Ontario, Canada. 3. It is shown that adult moths captured in early fall in Texas were immigrants from farther north, the first direct confirmation of a southward return migration of this species. Stable carbon isotope (δ13C) measurements indicated that spring immigrants in Ontario and autumn immigrants in Texas were from exclusively C3 biomes. Stable nitrogen isotope (δ15N) measurements also provided information on the probability of individuals coming from agriculturally intensive (i.e. higher δ15N) sites. Finally, several recommendations are provided regarding future research that could improve the Bayesian assignment models and thus improve assignment accuracy. [ABSTRACT FROM AUTHOR]

The recently discovered insect order Mantophasmatodea currently comprises 19 Southern African species. These mainly occur in allopatry, have high levels of color polymorphism and communicate via species- and gender-specific vibratory signals. High levels of interspecific morphological conservatism mean that cryptic species are likely to be uncovered. These aspects of Mantophasmatodean biology make them an ideal group in which to investigate population divergence due to habitat-specific adaptation, sexual selection, and potentially sensory speciation. Lack of appropriate genetic markers has thus far rendered such studies unfeasible. To address this need, the first microsatellite loci for this order were developed. Fifty polymorphic loci were designed specifically for Karoophasma biedouwense (Austrophasmatidae), out of which 23 were labeled and tested for amplification across the order using 2-3 individuals from 10 species, representing all 4 currently known families. A Bayesian mitochondrially encoded cytochrome c oxidase I (COI) topology was reconstructed and divergence dates within the order were estimated for the first time. Amplification success and levels of polymorphism were compared with genetic divergence and time since divergence. In agreement with studies on vertebrate taxa, both amplification and variability were negatively correlated with distance (temporal and genetic). The high number of informative loci will offer sufficient resolution for both broad level population genetic analysis and individual based pedigree or parentage analyses for most species in Austrophasmatidae, with at least some loci available for the other families. This resource will facilitate research into the evolutionary biology of this understudied but fascinating group. [ABSTRACT FROM AUTHOR]

Swarm-founding wasps are endemic and common representatives of neotropical fauna and compose an interesting social tribe of vespids, presenting both complex social characteristics and uncommon traits for a eusocial group, such as the absence of castes with distinct morphology. The paper wasp Protonectarina sylveirae (Saussure) presents a broad distribution from Brazil, Argentina and Paraguay, occurring widespread in the Atlantic rainforest and arboreal Caatinga, being absent in the Amazon region. Given the peculiar distribution among swarm-founding wasps, an integrative approach to reconstruct the evolutionary history of P. sylveirae in a spatial-temporal framework was performed to investigate: the presence of genetic structure and its relationship with the geography, the evolution of distinct morphologic lineages and the possible historical event(s) in Neotropical region, which could explain the observed phylogeographic pattern. Individuals of P. sylveirae were obtained from populations of 16 areas throughout its distribution for DNA extraction and amplification of mitochondrial genes 12S, 16S and COI. Analysis of genetic diversity, construction of haplotype net, analysis of population structure and dating analysis of divergence time were performed. A morphometric analysis was also performed using 8 measures of the body of the adult (workers) to test if there are morphological distinction among populations. Thirty-five haplotypes were identified, most of them exclusively of a group and a high population structure was found. The possibility of genetic divergence because of isolation by distance was rejected. Morphological analysis pointed to a great uniformity in phenotypes, with only a small degree of differentiation between populations of south and the remaining. Divergence time analysis showed a Middle/Late Miocene origin, a period where an extensive marine ingression occurred in South America. Divergence of haplogroups began from the Plio/Pleistocene boundary and the last glacial maximum most likely modeled the current distribution of species, even though it was not the cause of genetic breaks. [ABSTRACT FROM AUTHOR]

Thousand Island Lake (TIL) is a fragmented landscape consisting of more than 1000 land-bridge islands isolated during reservoir formation. To evaluate the effects of fragmentation and island attributes on insect populations, we examined the genetic structure ofLoxoblemmus aomoriensis, a species of cricket widely distributed in TIL, and compared genetic diversity between islands samples. Population genetic analyses was conducted based on mitochondrial DNA haplotype frequencies of 10 sample islands. By comparing three island attributes with population genetic diversity reveals that island area influenced population genetic diversity (r2 = 0.5094,p = 0.00204). Using Pairwise Fst values, we also found that long-distance isolation increased the genetic differentiation, while short-distance isolation can be offset by dispersal. These results indicate that fragmentation can impact populations on a genetic level. [ABSTRACT FROM AUTHOR]

A denaturing gradient gel electrophoresis assay was used to assess the genetic diversity within a region of the DNA polymerase gene (dnapol) in Helicoverpa armigera nucleopolyhedrovirus (HearNPV) populations over serial in vivo passages. There was no evidence of movement towards a consensus dnapol variant composition in the different host larvae after multiple per os passages. The study showed that the HearNPV variant structure after in vivo passages in the same host population is not necessarily convergent, and that it may be reasonable to expect significant differences in intra-host HearNPV genetic diversity after inoculation of larvae with a genotypically-diverse HearNPV inoculum. [ABSTRACT FROM AUTHOR]

The spread of adaptive genetic variants in populations is a cornerstone of evolutionary theory but with relatively few biologically well-understood examples. Previous work on the ls-tim variant of timeless, which encodes the light-sensitive circadian regulator in Drosophila melanogaster, suggests that it may have originated in southeastern Italy. Flies characterized by the new allele show photoperiod-related phenotypes likely to be adaptive in seasonal environments. ls-tim may be spreading from its point of origin in Italy by directional selection, but there are alternative explanations for its observed clinal geographical distribution, including balancing selection and demography. From population analyses of ls-tim frequencies collected on the eastern side of the Iberian Peninsula, we show that ls-tim frequencies are inverted compared with those in Italy. This pattern is consistent with a scenario of directional selection rather than latitude-associated balancing selection. Neutrality tests further reveal the signature of directional selection at the ls-tim site, which is reduced a few kb pairs either side of ls-tim. A reanalysis of allele frequencies from a large number of microsatellite loci do not demonstrate any frequent ls-tim-like spatial patterns, so a general demographic effect or population expansion from southeastern Italy cannot readily explain current ls-tim frequencies. Finally, a revised estimate of the age of ls-tim allele using linkage disequilibrium and coalescent-based approaches reveals that it may be only 300 to 3000 years old, perhaps explaining why it has not yet gone to fixation. ls-tim thus provides a rare temporal snapshot of a new allele that has come under selection before it reaches equilibrium. [ABSTRACT FROM AUTHOR]

Abstract: Although theoretical studies have shown that the mixture strategy, which uses multiple toxins simultaneously, can effectively delay the evolution of insecticide resistance, whether it is the optimal management strategy under different insect life histories and insecticide types remains unknown. To test the robustness of this management strategy over different life histories, we developed a series of simulation models that cover almost all the diploid insect types and have the same basic structure describing pest population dynamics and resistance evolution with discrete time steps. For each of two insecticidal toxins, independent one‐locus two‐allele autosomal inheritance of resistance was assumed. The simulations demonstrated the optimality of the mixture strategy either when insecticide efficacy was incomplete or when some part of the population disperses between patches before mating. The rotation strategy, which uses one insecticide on one pest generation and a different one on the next, did not differ from sequential usage in the time to resistance, except when dominance was low. It was the optimal strategy when insecticide efficacy was high and premating selection and dispersal occur. [ABSTRACT FROM AUTHOR]

Background: Anopheles (Kerteszia) cruzii is the primary vector of human and simian malarias in Brazilian regions covered by the Atlantic Rainforest. Previous studies found that An. cruzii presents high levels of behavioural, chromosomal and molecular polymorphisms, which led to the hypothesis that it may be a complex of cryptic species. Here, An. cruzii specimens were collected in five sites in South-East Brazil located at different altitudes on the inner and coastal slopes of two mountain ranges covered by Atlantic Rainforest, known as Serra do Mar and Serra da Mantiqueria. Partial sequences for two genes (Clock and cpr) were generated and compared with previously published sequences from Florianópolis (southern Brazil). Genetic diversity was analysed with estimates of population structure (FST) and haplotype phylogenetic trees in order to understand how many species of the complex may occur in this biome and how populations across the species distribution are related. Results: The sequences from specimens collected at sites located on the lower coastal slopes of Serra do Mar (Guapimirim, Tinguá and Sana) clustered together in the phylogenetic analysis, while the major haplotypes from sites located on higher altitude and at the continental side of the same mountains (Bocaina) clustered with those from Serra da Mantiqueira (Itatiaia), an inner mountain range. These two An. cruzii lineages showed statistically significant genetic differentiation and fixed characters, and have high FST values typical of between species comparisons. Finally, in Bocaina, where the two lineages occur in sympatry, we found deviations from Hardy-Weinberg equilibrium due to a deficit of heterozygotes, indicating partial reproductive isolation. These results strongly suggest that at least two distinct lineages of An. cruzii (provisorily named "Group 1" and "Group 2") occur in the mountains of South-East Brazil. Conclusions: At least two genetically distinct An. cruzii lineages occur in the Atlantic Forest covered mountains of South-East Brazil. The co-occurrence of distinct lineages of An. cruzii (possibly incipient species) in those mountains is an interesting biological phenomenon and may have important implications for malaria prevalence, Plasmodium transmission dynamics and control. [ABSTRACT FROM AUTHOR]

Lysiphlebia japonica (Ashmead) is a predominant parasitoid of cotton-melon aphids in the fields of northern China with a proven ability to effectively control cotton aphid populations in early summer. For accurate normalization of gene expression in L . japonica using quantitative reverse transcriptase-polymerase chain reaction (RT-qPCR), reference genes with stable gene expression patterns are essential. However, no appropriate reference genes is L . japonica have been investigated to date. In the present study, 12 selected housekeeping genes from L . japonica were cloned. We evaluated the stability of these genes under various experimental treatments by RT-qPCR using four independent (geNorm, NormFinder, BestKeeper and Delta Ct) and one comparative (RefFinder) algorithm. We identified genes showing the most stable levels of expression: DIMT , 18S rRNA , and RPL13 during different stages; AK , RPL13 , and TBP among sexes; EF1A , PPI , and RPL27 in different tissues, and EF1A , RPL13 , and PPI in adults fed on different diets. Moreover, the expression profile of a target gene ( odorant receptor 1 , OR1 ) studied during the developmental stages confirms the reliability of the chosen selected reference genes. This study provides for the first time a comprehensive list of suitable reference genes for gene expression studies in L . japonica and will benefit subsequent genomics and functional genomics research on this natural enemy. [ABSTRACT FROM AUTHOR]

Cockchafers of the genus Melolontha (Coleoptera, Scarabaeidae) seem to have a strong effect on forest management by inducing significant losses in the forest stands. Monitoring of the occurrence of Melolontha is carried out in many European countries, and the detailed data are available. But there is still a lack of data of the genetic population structure of Melolontha species as well as appropriate genetic markers. Amplification of microsatellite loci, developed for Melolontha melolontha, was performed in the closely related species Melolontha hippocastani. We successfully amplified the same eight polymorphic markers in both species of Melolontha. Generally, more alleles (from 5 to 15) were obtained for M. melolontha markers, and considerably fewer alleles (from 2 to 7) were observed for M. hippocastani. The mean observed heterozygosities were 0.676 and 0.192 respectively. The microsatellite markers tested in this study could be successfully used to study the population genetics of M. hippocastani. [ABSTRACT FROM AUTHOR]

This study evaluated the influence of environmental heterogeneity on Anopheles darlingi genetic and morphometric traits at a microgeographic level. Specimens of An. darlingi collected from multiple municipalities in the Colombian malaria endemic region Urabá-Bajo Cauca and Alto Sinú (UCS) were analyzed using 13 microsatellite loci. Spatial genetic structure, population variation and wing geometric morphometric analyses were performed. Microsatellite results showed low genetic differentiation and high gene flow among populations; four highly admixed subpopulations were detected with no particular association to the municipalities. Wing geometric morphometrics analysis showed a subtle but significant difference in wing shape for El Bagre vs. Mutatá populations, possibly influenced by geographical distance. Discrimination among populations in the morphospace showed a slight separation of the Tierralta population. There was no significant correlation between the genetic and geographic or genetic and environmental distances. We hypothesize that environmental heterogeneity in the UCS region does not reach a threshold to affect population structure of An. darlingi . Another possibility is that microsatellites are not sensitive enough to detect existing structure. It remains to be determined which local factors govern phenotypic variation among these populations and how, or whether these may affect mosquito biology and transmission capacity. [ABSTRACT FROM AUTHOR]

The rapidly increasing rate of urbanization has a major impact on the ecology and evolution of species. While increased temperatures are a key aspect of urbanization ('urban heat islands'), we have very limited knowledge whether this generates differentiation in thermal responses between rural and urban populations. In a common garden experiment, we compared the thermal performance curves (TPCs) for growth rate and mortality in larvae of the damselfly Coenagrion puella from three urban and three rural populations. TPCs for growth rate shifted vertically, consistent with the faster-slower theoretical model whereby the cold-adapted rural larvae grew faster than the warm-adapted urban larvae across temperatures. In line with costs of rapid growth, rural larvae showed lower survival than urban larvae across temperatures. The relatively lower temperatures hence expected shorter growing seasons in rural populations compared to the populations in the urban heat islands likely impose stronger time constraints to reach a certain developmental stage before winter, thereby selecting for faster growth rates. In addition, higher predation rates at higher temperature may have contributed to the growth rate differences between urban and rural ponds. A faster-slower differentiation in TPCs may be a widespread pattern along the urbanization gradient. The observed microgeographic differentiation in TPCs supports the view that urbanization may drive life-history evolution. Moreover, because of the urban heat island effect, urban environments have the potential to aid in developing predictions on the impact of climate change on rural populations. [ABSTRACT FROM AUTHOR]

Tallgrass prairie habitats within North America have suffered severe fragmentation and habitat loss as land has been converted for agricultural purposes. Habitat loss and fragmentation can affect gene flow and the genetic structure of insect populations. Neoconocephalus bivocatus is a prairie obligate katydid found only in isolated prairie patches. We compared genetic diversity and population differentiation using AFLP markers in N. bivocatus and N. robustus, a grassland generalist that is not isolated to prairie fragments and occupies a more contiguous range. Similar levels of genetic diversity were present within populations of both species. While population genetic structure was found in both species, there was no relationship between assigned genotypes and sampling localities. This genetic structure may instead be evidence of a past barrier to gene flow that has since been removed. Genetic differentiation within both species was low, with no evidence of a correlation with geographic distance, indicating neither species is dispersal limited at these distances. We see no significant reduction in genetic diversity or genetic differentiation within N. bivocatus when compared to N. robustus. We therefore conclude that while N. bivocatus utilizes a fragmented landscape, long-distance dispersal likely maintains gene flow between isolated prairie patches. [ABSTRACT FROM AUTHOR]

Background: Populations of the earthworm, Lumbricus rubellus, are commonly found across highly contaminated former mine sites and are considered to have under-gone selection for mitigating metal toxicity. Comparison of adapted populations with those found on less contaminated soils can provide insights into ecological processes that demonstrate the long-term effects of soil contamination. Contemporary sequencing methods allow for portrayal of demographic inferences and highlight genetic variation indicative of selection at specific genes. Furthermore, the occurrence of L. rubellus lineages across the UK allows for inferences of mechanisms associated with drivers of speciation and local adaptation. Results: Using RADseq, we were able to define population structure between the two lineages through the use of draft genomes for each, demonstrating an absence of admixture between lineages and that populations over extensive geographic distances form discrete populations. Between the two British lineages, we were able to provide evidence for selection near to genes associated with epigenetic and morphological functions, as well as near a gene encoding a pheromone. Earthworms inhabiting highly contaminated soils bare close genomic resemblance to those from proximal control soils. We were able to define a number of SNPs that largely segregate populations and are indicative of genes that are likely under selection for managing metal toxicity. This includes calcium and phosphatehandling mechanisms linked to lead and arsenic contaminants, respectively, while we also observed evidence for glutathione-related mechanisms, including metallothionein, across multiple populations. Population genomic end points demonstrate no consistent reduction in nucleotide diversity, or increase in inbreeding coefficient, relative to history of exposure. Conclusions: Though we can clearly define lineage membership using genomic markers, as well as population structure between geographic localities, it is difficult to resolve markers that segregate entirely between populations in response to soil metal concentrations. This may represent a highly variable series of traits in response to the heterogenous nature of the soil environment, but ultimately demonstrates the maintenance of lineage-specific genetic variation among local populations. L. rubellus appears to provide an exemplary system for exploring drivers for speciation, with a continuum of lineages coexisting across continental Europe, while distinct lineages exist in isolation throughout the UK. [ABSTRACT FROM AUTHOR]

Torymus sinensis Kamijo (Hymenoptera, Torymidae), a classical biocontrol agent of chestnut gall wasp Dryocosmus kuriphilus (Hymenoptera, Cynipidae), was released in Croatia, Slovenia and Hungary in 2015. Following the introduction, the research of parasitism rates and population genetic indices on 40 different sites was performed to monitor and evaluate the success of establishment. The observed parasitism rates were unexpectedly high and negatively correlated with the distance from westernmost locality, while population genetic indices showed that populations of T. sinensis did not suffer from bottleneck-induced founder effect phenomenon. Moreover, lack of genetic differentiation demonstrates that all populations share similar genetic structure, which could be shaped only by high levels of gene flow. We conclude that T. sinensis established viable and genetically diverse populations and successfully spread naturally from Italy across Slovenia to Croatia and Hungary. [ABSTRACT FROM AUTHOR]

The locally extinct dung beetle, Gymnopleurus mopsus Pallas, 1781 (Coleoptera: Scarabaeidae), has not been found in South Korea since the 1970s. This research was conducted to understand the genetic divergence between the South Korean and Mongolian populations of G. mopsus as a part of its reintroduction program in South Korea. The genetic distance and diversity were determined using the mitochondrial cytochrome c oxidase subunit I (COI) gene sequence (658 bp) corresponding to the DNA barcode region. The mitochondrial COI gene sequences of 64 individuals of G. mopsus collected in South Korea (7 individuals) and Mongolia (57 individuals) showed a relatively high level of genetic diversity (nucleotide diversity, 0.0078 ± 0.0007; Haplotype diversity, 0.965 ± 0.017). The genetic distances between the South Korean and Mongolian populations lay within the intraspecific level and the phylogenetic reconstruction using the neighbor-joining (NJ) method showed that all individuals belonged to a single clade. This result indicates that the current Mongolian population of G. mopsus is a good candidate source population to restore the locally extinct population of the species in South Korea. [ABSTRACT FROM AUTHOR]

Background: Glossina pallidipes is a major vector of both Human and Animal African Trypanosomiasis (HAT and AAT) in Kenya. The disease imposes economic burden on endemic regions in Kenya, including south-western Kenya, which has undergone intense but unsuccessful tsetse fly control measures. We genotyped 387 G. pallidipes flies at 13 microsatellite markers to evaluate levels of temporal genetic variation in two regions that have been subjected to intensive eradication campaigns from the 1960s to the 1980s. One of the regions, Nguruman Escarpment, has been subject to habitat alteration due to human activities, while the other, Ruma National Park, has not. In addition, Nguruman Escarpment is impacted by the movement of grazing animals into the area from neighboring regions during the drought season. We collected our samples from three geographically close sampling sites for each of the two regions. Samples were collected between the years 2003 and 2015, spanning ~96 tsetse fly generations. Results: We established that allelic richness averaged 3.49 and 3.63, and temporal Ne estimates averaged 594 in Nguruman Escarpment and 1120 in Ruma National Park. This suggests that genetic diversity is similar to what was found in previous studies of G. pallidipes in Uganda and Kenya, implying that we could not detect a reduction in genetic diversity following the extensive control efforts during the 1960s to the 1980s. However, we did find differences in temporal patterns of genetic variation between the two regions, indicated by clustering analysis, pairwise FST, and Fisher's exact tests for changes in allele and genotype frequencies. In Nguruman Escarpment, findings indicated differentiation among samples collected in different years, and evidence of local genetic bottlenecks in two locations previous to 2003, and between 2009 and 2015. In contrast, there was no consistent evidence of differentiation among samples collected in different years, and no evidence of local genetic bottlenecks in Ruma National Park. Conclusion: Our findings suggest that, despite extensive control measures especially between the 1960s and the 1980s, tsetse flies in these regions persist with levels of genetic diversity similar to that found in populations that did not experience extensive control measures. Our findings also indicate temporal genetic differentiation in Nguruman Escarpment detected at a scale of > 80 generations, and no similar temporal differentiation in Ruma National Park. The different level of temporal differentiation between the two regions indicates that genetic drift is stronger in Nugruman Escarpment, for as-yet unknown reasons, which may include differences in land management. This suggests land management may have an impact on G. pallidipes population genetics, and reinforces the importance of long term monitoring of vector populations in estimates of parameters needed to model and plan effective species-specific control measures. [ABSTRACT FROM AUTHOR]

Biological control of agricultural pests relies on knowledge of agroecosystem functionality, particularly when affected by the use of mass-produced biological agents. Incorporating pre- and/or post-release information such as genetic diversity and structure on these agents using molecular-based approaches could advance our knowledge of how they perform in agroecosystems. We evaluated the population genetics of Macrolophus pygmaeus, the most widely used predatory mirid against many arthropod pests of greenhouse crops in the Mediterranean region, using the mitochondrial Cytb sequence and microsatellite data, and population genetics and phylogeny approaches. We investigated commercially mass-produced insects (i.e., commercial insects either mass-reared in the laboratory for many generations, or purchased by farmers and released in the greenhouses) and 'wild' insects (i.e., that occur naturally outside or are collected in nature for release in the greenhouses). The mirids were mainly collected in agroecosystems in which solanaceous plants are grown in northern Spain, southern France and Greece. Both molecular markers and approaches distinguished 2 genetically differentiated populations. The less genetically diverse population, hereafter named the 'commercial' strain included all individuals from laboratory mass-rearings and most releases of commercially bred individuals. The most genetically diverse population mainly comprised individuals originating from noncultivated environments, or from releases of 'wild' individuals. Rare examples of hybridization between M. pygmaeus from the 2 populations were observed and asymmetric gene flow was revealed. These findings provide new insights into what happens to M. pygmaeus released in the agroecosystems we studied, and show that it is possible to monitor some commercial strains. [ABSTRACT FROM AUTHOR]

Orthotomicus erosus (Wollaston, 1857) (Coleoptera: Curculionidae: Scolytinae) is one of the principal pests of Eurasian forests. Gathering data from this study concerning population genetic structure of O. erosus would help improving new strategies to control the pest by giving new insights on forest management. The aims of the study were to resolve the population genetic structure of Orthotomicus erosus which distributes Mediterranean Region of Turkey and to determine the factors (such as host pine species and geographic barriers) that contributed to the current distribution of genetic diversity. The beetle samples were collected from 20 stands from the pine forests included in the Mediterranean Region of Turkey. 67 samples were studied using mitochondrial cytochrome oxidase subunit I (COI) gene and Neighbor Joining (NJ) and Maximum Likelihood (ML) analyses were performed. As a result of the study, thirty-seven distinct haplotypes from sixty-seven samples were determined. The species did not form any phylogroup in populations depending on the geographical location according to the NJ and ML analysis. The NJ and ML trees revealed that those O. erosus individuals that fed on different pine species did not have genetic variations. Consequently, NJ and ML analysis results reveals that different populations of the species across the Mediterranean Region were not disconnected and isolated geographically either. [ABSTRACT FROM AUTHOR]

The oriental fruit moth (OFM) Grapholita molesta (Lepidoptera: Tortricidae) is an important economic pest of stone and pome fruits worldwide. We sequenced the OFM genome using next-generation sequencing and characterized the microsatellite distribution. In total, 56,674 microsatellites were identified, with 11,584 loci suitable for primer design. Twenty-seven polymorphic microsatellites, including 24 loci with trinucleotide repeat and three with pentanucleotide repeat, were validated in 95 individuals from four natural populations. The allele numbers ranged from 4 to 40, with an average value of 13.7 per locus. A high frequency of null alleles was observed in most loci developed for the OFM. Three marker panels, all of the loci, nine loci with the lowest null allele frequencies, and nine loci with the highest null allele frequencies, were established for population genetics analyses. The null allele influenced estimations of genetic diversity parameters but not the OFM's genetic structure. Both a STRUCTURE analysis and a discriminant analysis of principal components, using the three marker panels, divided the four natural populations into three groups. However, more individuals were incorrectly assigned by the STRUCTURE analysis when the marker panel with the highest null allele frequency was used compared with the other two panels. Our study provides empirical research on the effects of null alleles on population genetics analyses. The microsatellites developed will be valuable markers for genetic studies of the OFM. [ABSTRACT FROM AUTHOR]

Quantitative real-time PCR (qRT-PCR) has been used extensively to analyze gene expression and decipher gene function. To obtain the optimal and stable normalization factors for qRT-PCR, selection and validation of reference genes should be conducted in diverse conditions. In insects, more and more studies confirmed the necessity and importance of reference gene selection. In this study, eight traditionally used reference genes in Galeruca daurica (Joannis) were assessed, using qRT-PCR, for suitability as normalization genes under different experimental conditions using four statistical programs: geNorm, Normfinder, BestKeeper and the comparative ΔCt method. The genes were ranked from the most stable to the least stable using RefFinder. The optimal suite of recommended reference genes was as follows: succinate dehydrogenase (SDHA) and tubulin-alpha (TUB-α) for temperature-treated larvae; ribosomal protein L32, SDHA and glutathione S-transferase were best for all developmental stages; ACT and TUB-α for male and female adults; SDHA and TUB-α were relatively stable and expressed in different tissues, both diapause and non-diapause adults. Reference gene evaluation was validated using expression of two target genes: the P450 CYP6 gene and the heat shock protein gene Hsp70. These results confirm the importance of custom reference gene selection when studies are conducted under diverse experimental conditions. A standardized qRT-PCR analysis procedure for gene functional studies is provided that could be useful in studies on other insect species. [ABSTRACT FROM AUTHOR]

Molecular methods that rely on microsatellite markers have been developed for population genetic studies and diagnostics of tephritid pest species such as the Mediterranean fruit fly, Ceratitis capitata (Wiedemann) (Diptera: Tephritidae). Whereas many of these markers are tested to see if they are within the Hardy-Weinberg equilibrium, very few markers developed for pest species are tested to ensure the selected alleles behave according to the laws of Mendelian inheritance. Fifteen previously developed microsatellite markers were examined for Mendelian inheritance. Nine parental groups consisting of a laboratory reared parent and a wild type parent and their respective progeny were examined. In total, 174 flies, consisting of 90 males and 84 females, were analyzed. Seventy-seven segregation ratio tests were performed to determine if any departures from expected Mendelian inheritance occurred. Representatives from each of the observed alleles were cloned and sequenced. Troubleshooting was performed on loci that did not conform to expected Mendelian inheritance ratios to confirm the cause and improve laboratory procedures. Issues observed included incomplete adenylation at the 5′ end in Ccmic3, the presence of artifactual bands leading to false calls in Ccmic25, and monomorphic alleles in Ccmic7. Only 1 locus, Ccmic25, deviated from Mendelian expectations after protocol optimization in the form of a detected transmission ratio distortion leading to excessive heterozygosity. Finally, 1 locus, Ccmic9, showed evidence of allelic homoplasy. [ABSTRACT FROM AUTHOR]

The renewed effort to eliminate malaria and permanently remove its tremendous burden highlights questions of what combination of tools would be sufficient in various settings and what new tools need to be developed. Gene drive mosquitoes constitute a promising set of tools, with multiple different possible approaches including population replacement with introduced genes limiting malaria transmission, driving-Y chromosomes to collapse a mosquito population, and gene drive disrupting a fertility gene and thereby achieving population suppression or collapse. Each of these approaches has had recent success and advances under laboratory conditions, raising the urgency for understanding how each could be deployed in the real world and the potential impacts of each. New analyses are needed as existing models of gene drive primarily focus on nonseasonal or nonspatial dynamics. We use a mechanistic, spatially explicit, stochastic, individual-based mathematical model to simulate each gene drive approach in a variety of sub-Saharan African settings. Each approach exhibits a broad region of gene construct parameter space with successful elimination of malaria transmission due to the targeted vector species. The introduction of realistic seasonality in vector population dynamics facilitates gene drive success compared with nonseasonal analyses. Spatial simulations illustrate constraints on release timing, frequency, and spatial density in the most challenging settings for construct success. Within its parameter space for success, each gene drive approach provides a tool for malaria elimination unlike anything presently available. Provided potential barriers to success are surmounted, each achieves high efficacy at reducing transmission potential and lower delivery requirements in logistically challenged settings. [ABSTRACT FROM AUTHOR]

Dendrothrips minowai Priesner (Thysanoptera: Thripidae) is one of the most destructive insect pests on tea plants. Although outbreaks of this pest occur annually in South China, especially in Guizhou Province, little is known about its population genetics, such as genetic diversity and gene flow. To investigate its population genetic structure and migration routes in Guizhou Province, we analyzed 24 D. minowai populations across Guizhou using six microsatellite loci. We detected the moderate genetic diversity and the population genetic structure of this thrip species. Neighbor-joining (NJ) phylogenetic tree and STRUCTURE analyses recognized two clusters within the studied populations. No correlation between genetic and geographical distances (r = 0.0139, P = 0.5830) was detected and more than 89% of the variation occurred among samples within populations. Gene flow analysis revealed high migration rates (74.0 - 894.1) among D. minowai populations. Overall, the trend of asymmetrical gene flow was from northeast to southwest. Our analyses demonstrated that D. minowai derived or originated from multiple sites and could be eventually divided into two groups in Guizhou. [ABSTRACT FROM AUTHOR]

Anopheles gambiae sensu stricto was recently reclassified as two species, An. coluzzii and An. gambiae s.s., in wild-caught mosquitoes, on the basis of the molecular form, denoted M or S, of a marker on the X chromosome. The An. gambiae Keele line is an outbred laboratory colony strain that was developed around 12 years ago by crosses between mosquitoes from 4 existing An. gambiae colonies. Laboratory colonies of mosquitoes often have limited genetic diversity because of small starting populations (founder effect) and subsequent fluctuations in colony size. Here we describe the characterisation of the chromosomal form(s) present in the Keele line, and investigate the diversity present in the colony using microsatellite markers on chromosome 3. We also characterise the large 2La inversion on chromosome 2. The results indicate that only the M-form of the chromosome X marker is present in the Keele colony, which was unexpected given that 3 of the 4 parent colonies were probably S-form. Levels of diversity were relatively high, as indicated by a mean number of microsatellite alleles of 6.25 across 4 microsatellites, in at least 25 mosquitoes. Both karyotypes of the inversion on chromosome 2 (2La/2L+a) were found to be present at approximately equal proportions. The Keele colony has a mixed M- and S-form origin, and in common with the PEST strain, we propose continuing to denote it as an An. gambiae s.s. line. [ABSTRACT FROM AUTHOR]

Combining a biotin-enrichment protocol and 454GS-FLX titanium pyrosequencing technology, we characterised 22 polymorphic microsatellite loci from the parasitic wasp, Habrobracon hebetor (Say) (Hymenoptera: Braconidae), a cosmopolitan species commonly used in biological control against a wide range of both major lepidopterous pests of stored products and field crops in different parts of the world. Three multiplex PCR sets were optimised and characterised across 46 H. hebetor specimens from two samples collected from millet fields in Niger. Two to 11 alleles were found per locus and observed heterozygosity ranged from 0.289 to 0.826. Polymorphism was detected in both samples with a similar level of observed heterozygosity (0.482 vs. 0.502) and number of alleles (4.1 vs. 3.6). Deviation from Hardy-Weinberg equilibrium was detected at the same five loci in both samples and five or seven more loci in each sample but was not associated with heterozygote deficiencies. Even though evidence for linkage disequilibrium was found between a few alleles, these new loci segregated independently. The variability of the 22 loci will enable estimates of genetic diversity and structure patterns, as well as gene flow between H. hebetor populations at different spatial scales. Cross-species amplifications were successful among the six Bracon spp. tested and nine loci will be particularly appropriate for population genetic studies in B. brevicornis. [ABSTRACT FROM AUTHOR]

The pattern of genetic variation in a butterfly species depends on the past history of the given species and also on recent evolutionary processes affecting its populations. The aim of the present study was (i) to analyse the enzyme polymorphism in the Clouded Apollo populations of the Carpathian Basin to reveal the contemporary pattern of their genetic differentiation and (ii) to compare it with an expanded mitochondrial DNA (mtDNA) haplotype network of the SE European populations. Allozyme polymorphism was analysed in 22 populations of four geographic regions: Transdanubian (TM) and North Hungarian Mountains (NM), Körös (KÖR) and Bereg-Apuseni-East Carpathian regions (BEAC). The results of the Bayesian clustering analyses based on allozymes supported the presence of three main genetic lineages in the Carpathian Basin: One was typical for TM, another was characteristic for NM and the third cluster was predominant in KÖR. The populations of BEAC harboured a mixture of two clusters. The mtDNA haplotype network suggested a fairly similar distribution: The peri-Alpine clade together with the West Balkan clade was detected in TM, while the East Balkan clade occurred in NM, partly in TR and in the two eastern regions of the Basin (KÖR and BAEC). The incongruities between the results of the mtDNA and allozyme studies can be explained by the different timescales represented by the two markers. The mtDNA haplotype network provided strong evidence concerning the existence of two Balkan lineages, which probably formed a 'zone of admixture' in the Transdanubian and North Hungarian Mountains. The possibility of Last Glacial survival of Parnassius mnemosyne in the Carpathian Basin and the conservation implications of these results are discussed. [ABSTRACT FROM AUTHOR]

Together with reduction in habitat area and quality, reduction in habitat connectivity is one of the major factors influencing species' persistence in fragmented landscapes. We explore the consequences of recent habitat fragmentation on volcanoes across Isabela Island, Galápagos by analyzing genetic patterns of populations of endemic weevils whose host plants have been depleted by indiscriminate goat grazing. We predicted that if grazing on the weevils' host plants has caused habitat fragmentation on the weevils populations themselves, then the effects on the genetic architecture of populations should be more severe on Galapaganus conwayensis populations from volcanoes on Northern Isabela than on those from Santa Cruz or Pinta islands where vegetation destruction was not as extensive. We used mitochondrial sequences to reveal historical colonization patterns and microsatellite variation to understand more contemporary genetic changes. We found significantly lower microsatellite genetic diversity and population size within localities and increased genetic differentiation at a small geographic scale with a stronger isolation by distance pattern and larger numbers of genetic clusters on Isabela. In the absence of long-standing mitochondrial structure within each volcano, we interpret the microsatellite results as suggesting that recent host plant habitat fragmentation may indeed influence the genetic patterns of plant feeding insects and highlight the importance of controlling the spread of introduced herbivores in the Galápagos Islands. [ABSTRACT FROM AUTHOR]

Workers in insect societies are sometimes observed to kill male eggs of other workers, a phenomenon known as worker policing. We perform a mathematical analysis of the evolutionary dynamics of policing. We investigate the selective forces behind policing for both dominant and recessive mutations for different numbers of matings of the queen. The traditional, relatedness-based argument suggests that policing evolves if the queen mates with more than two males, but does not evolve if the queen mates with a single male. We derive precise conditions for the invasion and stability of policing alleles. We find that the relatedness-based argument is not robust with respect to small changes in colony efficiency caused by policing. We also calculate evolutionarily singular strategies and determine when they are evolutionarily stable. We use a population genetics approach that applies to dominant or recessive mutations of any effect size. [ABSTRACT FROM AUTHOR]

Our understanding of the systematics of the Eurytemora affinis complex developed at a fast pace over the last decades. Formerly considered as a complex of cryptic species, it is now believed to include three valid species: E. affinis , Eurytemora carolleeae , and Eurytemora caspica . American and European representatives have been studied in detail with respect to fine-scale geographic distribution, levels of genetic subdivision, evolutionary and demographic histories. Morphological components have been less explored. In this study, an analysis of the phylogeny and morphology of E. affinis was done, with a special focus on European populations. A total of 447 individuals of E. affinis from Europe were analyzed with genetic tools and 170 individuals according to morphological criteria. Common and new morphological and genetic features were analyzed. For this, we used ML and Bayesian methods to analyze the bar coding mt-DNA gene cytochrome c oxidase I subunit. Both genetic and morphological analyses showed high heterogeneities among the E. affinis populations from Europe. As a result, three local populations of E. affinis in Western Europe, including the European part of Russia, were established. Their genetic and morphological heterogeneity corresponded to the subspecies level. [ABSTRACT FROM AUTHOR]

Sterile male releases have successfully reduced local populations of the dengue vector, Aedes aegypti , but challenges remain in scale and in separating sexes before release. The recent discovery of the first mosquito male determining factor (M factor) will facilitate our understanding of the genetic programs that initiate sexual development in mosquitoes. Manipulation of the M factor and possible intermediary factors may result in female-to-male conversion or female killing, enabling efficient sex separation and effective reduction of target mosquito populations. Given recent breakthroughs in the development of CRISPR-Cas9 reagents as a source of gene drive, more advanced technologies at driving maleness, the ultimate disease refractory phenotype, become possible and may represent efficient and self-limiting methods to control mosquito populations. [ABSTRACT FROM AUTHOR]

Lasioderma serricorne (F.) is a small cosmopolitan beetle regarded as a destructive pest of several stored products such as grains, flour, spices, dried fruit and tobacco. Chemical insecticides are one of the measures used against the pest. However, intensive insecticide use has resulted in the appearance of resistant insect populations. Therefore, for the elaboration of more effective control programs, it is necessary to know the biological aspects of L. serricorne. Among these aspects, the genetic variability knowledge is very important and may help in the development of new control methods. The objective of this study was to evaluate the genetic variability of 11 natural populations of L. serricorne collected respectively in three and four towns in the states of Paraná and São Paulo, Brazil, using 20 primers random amplified polymorphic DNA (RAPD) and polymorphisms of esterases. These primers produced 352 polymorphic bands. Electrophoretic analysis of esterases allowed the identification of four polymorphic loci (Est-2, Est-4, Est-5 and Est-6) and 18 alleles. Results show that populations are genetically differentiated and there is a high level of genetic variability within populations. The high degree of genetic differentiation is not directly correlated to geographical distance. Thus, our data indicate that movement of infested commodities may contribute to the dissemination of L. serricorne, facilitating gene flow. [ABSTRACT FROM PUBLISHER]

The taxonomic status of subspecies has long been debated, especially in conservation biology. Some proposed subspecies must be evolutionarily distinct to be considered conservation units. White-necklaced Partridge (Arborophila gingica) comprises two subspecies, A. g. gingica and A. g. guangxiensis. A. g. guangxiensis, restricted to three isolated small areas in Guangxi, China, with limited population sizes, is a newly discovered subspecies based on recently identified geographic and phenotypic differences between A. g. gingica; however, evidence is lacking that can effectively identify whether the subspecies is evolutionarily distinct. Here, three mitochondrial DNA segments and four nuclear introns were used to test whether the two subspecies are reciprocally monophyletic, which has been proposed as an objective method to evaluate evolutionary distinctiveness. The results indicate that the two subspecies are genetically divergent and form reciprocal monophyletic groups. Therefore, this study further supports the taxonomic validity and distinctiveness of A. g. guangxiensis and suggests that this subspecies be considered as a conservation unit. [ABSTRACT FROM AUTHOR]

We characterized fifteen microsatellite markers for the butterfly Maniola jurtina . For the six studied populations (96 samples) the total number of alleles per locus ranged from 3 to 55 and mean overall expected heterozygosity across all loci was 0.74. In spite of a high frequency of null alleles detected in part of the loci, a recurrent phenomenon in Lepidopteron, the estimation of pairwise F ST seems rather insensitive to the presence of these null alleles as shown by the high correlation between F ST calculated after correction for the presence of null alleles and non-corrected F ST , indicating that the loci may be usable in population genetics, more specifically for the study of populations genetics structure. [ABSTRACT FROM AUTHOR]

The socially parasitic Phengaris arion is one of the most threatened butterfly species in Europe. Using 12 microsatellite loci, we studied the genetic structure of 14 ecologically diverse populations (285 individuals) originating from two distinct areas of the European distribution range (Poland and Italy)., Italian populations were more differentiated ( FST = 0.124) than Polish populations (0.073). Nevertheless, in contrast to the results of previous studies on mitochondrial ( COI) and nuclear ( EF-1α) genes, indices of genetic variability were higher in Poland. Within-population genetic variability in Italy decreased southwards, whereas in Poland no similar gradient of changes was detected., Bayesian clustering of individuals ( STRUCTURE, BAPS) and analysis of principal components ( PCA) indicated a genetic structure in Italian sampling sites that was more pronounced than in Poland. The analysis also suggested a common evolutionary history for populations inhabiting the northern slopes of the Alps and Central Europe, or that the alpine populations are localised in a mixed zone of different post-glacial colonisation routes ( STRUCTURE, PCA). In addition, implementation of spatial information into the analysis ( BAPS) suggested that the observed pattern of differentiation could be shaped simply by landforms as all Italian sampling sites and two mountainous Polish sites formed separate cluster., The pattern of ecological variation did not influence genetic structure and no grounds for separation of subspecies ( P. arion ligurica and P. arion obscura) were found. Our results are therefore in agreement with conclusions inferred from other studies carried out in Europe on P. arion. [ABSTRACT FROM AUTHOR]

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The White Mountain arctic butterfly [WMA; Oeneis melissa semidea (Say)] is endemic to the alpine zone of Mts. Washington and Jefferson, New Hampshire, USA, and because of its small and declining population size, it is considered threatened. White Mountain arctic adults occur only within four alpine meadows, and it has been suggested that dispersal, and hence gene flow, may be restricted among these meadow subpopulations. Furthermore, although the WMA likely is biennial (i.e., requires 2 years for development) like all other species of Oeneis, adults emerge annually. Thus the WMA population may be further structured into two allochronic cohorts, reproductively isolated by their asynchronous adult emergence in either even- or odd-numbered years. We assessed the spatial (among meadows) and temporal (between even- and odd-year cohorts) genetic structure and diversity of the WMA using mtDNA and AFLP markers generated from non-lethally sampled wing and leg tissue. We found no evidence for restricted gene flow among meadows. AFLPs indicated weak differentiation between alternate year cohorts; however, it remains unclear whether this resulted from allochronic reproductive isolation or genetic drift. Despite the WMA's small population size and isolation, levels of AFLP genetic diversity were generally high. Rather than focusing on factors related to population connectivity and adult dispersal, our results suggest that management efforts for the WMA should instead focus explicitly on factors affecting recruitment and mortality. [ABSTRACT FROM AUTHOR]

The article presents a study that deals with the genetic diversity and affinity of Philaenus spumarius populations from southwestern Asia. The study reveals a high level of genetic diversity within Turkish and Iranian populations, and significant differences in the distribution and amount of heterochromatin compared to other populations.

Niphanda fusca is an endangered myrmecophilous butterfly inhabiting environments at early stages of succession. Most of its habitats are places where succession is prevented by human activity. In some places, however, N. fusca lives in natural semi-bare areas, such as cliffs in mountains or grasslands around volcanos. We investigate the genetic structure of N. fusca in Japan and South Korea to address two questions. (1) Are populations in natural environments genetically different from those in secondary environments? and (2) Do populations in natural environments possess greater genetic diversity than those in secondary environments? The AMOVA results indicated that the populations in natural environments and those in secondary environments were differentiated to some extent; however, more than 80 % of genetic variation was found to occur within the same habitat type and within each population. We found no differences in genetic diversity between populations in the two environments. At present, we have not found a strong reason to consider populations in the two environments as different evolutionarily significant units. We think it is practical to conserve populations in natural environments at first, because in this case we need not manage habitats to protect N. fusca. We have only to inhibit habitat destruction. In contrast, in order to conserve populations in secondary environments, we would have to continue managing the habitats. This is far more difficult than inhibiting habitat destruction. [ABSTRACT FROM AUTHOR]