Fine scale population structure of hoverfly pollinator, <i>Eristalis arbustorum</i>:An integrative study

Determination of the factors influencing the population structure and adaptive tolerance to environmental pressures of the synanthropic hoverfly Eristalis arbustorum is of essential importance in understanding how pollinator populations could respond to climate change or ecosystem management. We addressed the issue of connectivity among conspecific populations sampled in Bosnia and Herzegovina. Twenty environmental factors, mitochondrial DNA sequences of the cytochrome c oxidase subunit I gene (COI mtDNA), allele frequencies at allozyme loci and wing traits (size and shape) were compared for characterization of population structure and environmental niches. Additionally, patterns of within-individual asymmetry (fluctuating asymmetry; FA) in wing size and shape within and among conspecific populations were studied. In line with the overall similarity of the environmental factors extracted for our study sites, the results of COI mtDNA diversity and STRUCTURE allozyme data provide evidence for shallow differentiation among conspecific populations. In contrast, geo-referenced Bayesian clustering methods (BAPS and GENELAND) and population-based approaches (pairwise F-ST values and AMOVA) indicate that the dispersal potential of E. arbustorum may be limited across the study area. Along with a significant FA in wing size and shape, a consistent level of FA regardless of urban/rural sampling origin is an indication of the great potential of E. arbustorum for local adaptation, because increased FA levels can be considered to be a way of expression of phenotypic variation and, hence, may contribute to adaptive responses in populations facing changing environments. Thus, by using a combined genetic-morphological approach, we significantly contributed to the understanding of the fine-scale genetic structure of the synanthropic generalist pollinator E. arbustorum

Integrative study of population structure of <i>Telestes dabar</i>, the strictly endemic cyprinid species from the Dinaric karst on the Balkan Peninsula

Diversification of the genus Telestes (Cyprinidae), endemic to the Euro-Mediterranean biogeographic subregion, mirrored an evolutionary footprint of complex biogeographical history. Hence, hidden diversity and noticeably high endemicity of freshwater ichthyofauna were discovered in the Dinaric karst on the Balkan Peninsula. One such example includes two steno-endemic Dinaric karst (Bosnia and Herzegovina) cyprinid species, Telestes dabar and T. metohiensis. Although the conservation status of T. metohiensis has been evaluated, T. dabar from Dabarsko Polje has not yet been assessed for the IUCN Red List due to its taxonomically ambiguous position and data deficiencies. Our first aim was to evaluate the resolution of taxonomic ambiguities of the two putative species, T. dabar and T. metohiensis, by the complementary use of two mitochondrial DNA markers (cytb and COI mtDNA). The results clearly demonstrated the evolutionary independence of T. dabar (Dabarsko Polje) and T. metohiensis (Nevesinjsko Polje) and confirmed the usefulness of both markers for assessing the species borders. In addition, population structure of putative T. dabar was analyzed using cytb and COI mtDNA and morphological parameters (linear measurements and landmark-based geometric morphometric data). A high genetic admixture and homogeneity in T. dabar from Dabarsko Polje were found and confirmed using both morphometric approaches as no statistically significant differences were consistently registered between different samples

DNA barcode assessment and population structure of aphidophagous hoverfly Sphaerophoria scripta: Implications for conservation biological control

With the advent of integrated pest management, the conservation of indigenous populations of natural enemies of pest species has become a relevant practice, necessitating the accurate identification of beneficial species and the inspection of evolutionary mechanisms affecting the long-time persistence of their populations. The long hoverfly,Sphaerophoria scripta, represents one of the most potent aphidophagous control agents due to a worldwide distribution and a favorable constellation of biological traits. Therefore, we assessed five EuropeanS. scriptapopulations by combining molecular (cytochromecoxidase subunit I-COI, internal transcribed spacer 2-ITS2, and allozyme loci) and morphological (wing size and shape) characters.COIsequences retrieved in this study were conjointly analyzed with BOLD/GenBank sequences of the otherSphaerophoriaspecies to evaluate whetherCOIpossessed a sufficient diagnostic value as a DNA barcode marker to consistently delimit allospecific individuals. Additionally, the aforementioned characters were used to inspect the population structure ofS. scriptain Europe using methods based on individual- and population-based genetic differences, as well as geometric morphometrics of wing traits. The results indicate numerous sharedCOIhaplotypes among differentSphaerophoriaspecies, thus disqualifying this marker from being an adequate barcoding region in this genus. Conversely, the analyses of population structuring revealed high population connectivity across Europe, therefore indicating strong tolerance ofS. scriptato environmental heterogeneity. The results imply a multilocus approach as the next step in molecular identification of differentSphaerophoriaspecies, while confirming the status ofS. scriptaas a powerful biocontrol agent of economically relevant aphid pests