Many species of river riparia are threatened by habitat loss due to altered flood and sediment regime, and associated shifts in vegetation structure. However, their ecological niche is often obscure, especially in inconspicuous organisms such as lichens, hindering their conservation and use as indicator species in river restoration. We studied if variation in sediment size distribution, gravel bank elevation and vegetation str...

Large phylogeographic studies on lichens are scarce, and none involves a single species within which different lineages show fixed alternative dispersal strategies. We investigated Bryoria fuscescens (including B . capillaris ) in Europe and western North Africa by phenotypically characterizing 1400 specimens from 64 populations and genotyping them with 14 microsatellites. We studied population structure and genetic diversity...

During the evolution of the lichen symbiosis, shifts from one main type of photobiont to another were infrequent (Miadlikowska et al . ) but some remarkable transitions from green algal to diazotrophic cyanobacterial photobionts are known from unrelated fungal clades within the ascomycetes. Cyanobacterial, including tripartite, associations (green algal and cyanobacterial photobionts in one lichen individual) facilitate these...

Population genetics of the tree‐colonizing lichen L obaria pulmonaria were studied in the largest primeval beech forest of E urope, covering 10 000 ha. During an intensive survey of the area, we collected 1522 thallus fragments originating from 483 trees, which were genotyped with eight mycobiont‐ and 14 photobiont‐specific microsatellite markers. The mycobiont and photobiont of L . pulmonaria were found to consist of two dist...

In lichen symbiosis, fungal and algal partners form close associations, often codispersed by vegetative propagules. Due to the particular interdependence, processes such as colonization, dispersal or genetic drift are expected to result in congruent patterns of genetic structure in the symbionts. To study the population structure of an obligate symbiotic system in E urope, we genotyped the fungal and algal symbionts of the epi...

Epiphytes are strongly affected by the population dynamics of their host trees. Owing to the spatio‐temporal dynamics of host tree populations, substantial dispersal rates — corresponding to high levels of gene flow — are needed for populations to persist in a landscape. However, several epiphytic lichens have been suggested to be dispersal‐limited, which leads to the expectation of low gene flow at the landscape scale. Here,...

Lichens associated with old forest are commonly assumed to be negatively affected by tree logging or natural disturbances. However, in this study performed in a spruce‐dominated sylvopastoral landscape in the Swiss Jura Mountains, we found that genetic diversity of the epiphytic old‐forest lichen Lobaria pulmonaria depends on the type of disturbance. We collected 923 thalli from 41 sampling plots of 1 ha corresponding to the c...

In the search for cost‐effective methods for measuring and monitoring lichen diversity, we tested the performance of two possible indicators: lichen genus diversity and macrolichen diversity. We studied the lichen vegetation of eight European countries situated in six different biogeographic regions. In each country, six land‐use units (each 1 km 2 ) representing a land‐use gradient ranging from old‐growth forest to farmland w...

Many lichen species produce both sexual and asexual propagules, but, aside from being minute, these diaspores lack special adaptations for long‐distance dispersal. So far, molecular studies have not directly addressed isolation and genetic differentiation of lichen populations, both being affected by gene flow, at a regional scale. We used six mycobiont‐specific microsatellite loci to investigate the population genetic structu...