Phenotypic diversity and landscape genetics of eristalis tenax in a spatially heterogeneous environment, Durmitor mountain (Montenegro)

摘要

The study of the spatial distribution of phenotypic and genetic diversity of pollinators has conservation implications since pollination is a key ecosystem function and a basis for the maintenance of biodiversity. The impact of landscape heterogeneity on the population structure of the important hoverfly pollinator, Eristalis tenax (Diptera, Syrphidae), was investigated. Allele frequencies at allozyme loci, wing traits (size and shape) and abdominal colour pattern were compared using samples from eight locations in the Durmitor National Park, Montenegro. These locations covered a broad range of altitudes and vegetation structures, from deciduous and coniferous forests to alpine meadows. From the conservation point of view, we investigated to what extent the localities in the Durmitor mountain range are connected. Results indicated a lack of population structure in the study area. A genetic clustering analyses based on Bayesian model revealed no resolution among samples, coinciding with FST estimates. Weak genetic differentiation was accompanied by wing size and shape similarity. In addition, there was an overlap between the levels of abdominal colour variation among samples supporting the negative association between gene flow and phenotypic divergence in E. tenax. We conclude that the surrounding landscape is of no relevance to the species movement capabilities. The availability of many sites for E. tenax and its strong dispersal capacity might make the study region a more or less continuous habitat for this species. Thus, our results may contribute to understanding the potential extent to which E. tenax can facilitate gene flow among isolated plant populations on Mt. Durmitor.