Bryophytes are typically seen as extremely efficient dispersers. Experimental evidence suggests that efficient short‐distance dispersal coupled with random long‐distance dispersal (LDD) leads to an inverse isolation effect. Under the latter, a higher genetic diversity of colonizing propagules is expected with increasing isolation, counteracting differentiation beyond the range of short‐distance dispersal. This expectation is tested from a review of evidence on spatial genetic structure and analyses of isolation‐by‐distance (IBD) at different scales. A decay of the IBD signal, characterized by non‐significant slopes between kinship coefficients and geographic distance was observed beyond 100 m. A second slope shift was observed at distances larger than 1 km, with a proportion of significant slopes in more than one third of the datasets. The decay of the IBD signal beyond 100 m, which reflects efficient LDD, is consistent with the inverse isolation hypothesis. Persistence of a significant IBD signal at medium ranges in one third of the analysed cases suggests, however, that the inverse isolation effect is not a rule in bryophyte spore dispersal. Furthermore, the higher proportion of significant IBD patterns observed at scales over 100 km likely marks the limits of regional dispersal, beyond which an increasingly smaller proportion of spores travel. Synthesis. We discuss the differences between experimental and genetic estimates of spore dispersal and conclude that geographic distance remains a significant proxy of spore colonization rates, with major consequences for our understanding of actual migration capacities in bryophytes, and hence, our capacity to model range shifts in a changing world.

Rare epixylic moss Buxbaumia viridis, which is one of the "Annex II" species of the European "Habitat directive", has been recorded at 124 localities in the Czech Republic in course of the last 13 years. Most of them were discovered in the last five years following a dedicated search at both historical sites of occurrence and new localities with putatively suitable habitat conditions. The recent and historical area of occupancy and extent of occurrence are not obviously different, although most of the recent localities are concentrated in the Western Carpathians and the Hrubý Jeseník Mts. Surprisingly, only 38% of the localities are located in natural forest habitats, of which herb-rich and acidophilous beech forests were among the most commonly inhabited ones. The rest of occurrences were recorded in non-natural forests (habitats strongly influenced or created by man), particularly the coniferous forest plantations. Sufficient amount of decaying wood of the advanced decay stages, as well as sufficient and constant humidity are crucial prerequisites for the occurrence of B. viridis in both types of forests. True epixylic moss Herzogiella seligeri and the liverwort Chiloscyphus profundus were recorded as the most common associated species, while the rest of commonly co-occurring species were facultatively epixylic, ground or ubiquitous bryophytes; other specialized and rare epixylic mosses or liverworts were only rarely recorded. We also designed a potential distribution model for B. viridis based on the distribution of habitats most commonly occupied by the studied moss. Despite the simplicity of the model, its close match with the recent distribution in the Western Carpathians, the Hrubý Jeseník Mts. and Šumava Mts. supports its relevance for the real distribution of B. viridis.

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Scapania undulata is an aquatic dioicous liverwort growing in shallow streams in boreal to subtropical zones. We studied the expressed sex ratio, sex-specific differences in shoot architecture and possible trade-off between sexual and asexual reproduction in ten populations of S. undulata by surveying 100 plots in ten streams in southern Finland. The expressed sex ratio was male biased, in contrast with the sex ratio in most dioicous bryophytes. It was also highly variable between the streams, but individual plots frequently comprised shoots from only one sex. The overproduction of males might be a strategy to overcome sperm dilution and ensure fertilization over longer distances in water. No size differences between females and males were detected, but they differed in branching patterns. Evidence for a higher cost of sexual reproduction in females than males can be seen from the following: the male-biased sex ratio; low number of sex-expressing female shoots in female-only plots; no co-occurrence of gemmae and female sex organs on a single branch, and no more than one sexual branch per female shoot. In contrast, high gemma production of male and female sex-expressing shoots indicates a minimal trade-off between sexual and asexual reproduction.

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