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Bryophytes are important elements of plant communities in most habitat types worldwide. However, due to their relatively small size and difficult identification, bryophyte data are missing in many plant community studies. The objective of the present study is to increase the knowledge about EU Habitat directive bryophyte species distribution and conservation in Latvia. We compiled data from the Natural Data Management System OZOLS database about four EU Habitat Directive bryophyte species: Buxbaumia viridis, Dicranum viride, Hamatocaulis vernicosus and H. lapponicus, all indicators of high–value habitats in Latvia. The most common EU Habitat Directive species in this group was Buxmaumia viridis, which showed a significantly higher occurrence in the Western taiga habitat. Most of Hamatocaulis lapponicus and H. vernicosus localities were registered in protected areas with a high and moderate degree of protection. Most of Buxbaumia viridis and Dicranum viride localities were registered outside of the protected areas with a low degree of protection. Our results showed that EU Habitat Directive bryophyte species conservation in the long–term in Latvia is unclear, especially for B. viridis and D. viride populations. In future studies, we recommend initiating large-scale protected bryophyte monitoring programs and population studies that could contribute to plant community and global climate change research. [ABSTRACT FROM AUTHOR]

The geographical distributions of the two cryptic species of the wetland moss Hamatocaulis vernicosus were mapped for western, central and northern Europe, based on identifications of the two by the nuclear ITS1 + 2 and the plastid rpl16 and trnL–trnF. The distributions of the two cryptic species overlap to a large extent. However, in the west and south-west only cryptic species 1 is present, whereas in the boreal north only cryptic species 2 occurs, which agrees with its distribution in Scandinavia. Despite these differences in distribution, no differences between the two cryptic species were revealed in habitat water chemistry, elevation distribution or climatic niches. The difference in distribution therefore suggests that cryptic species 1 could have survived the glacial period in southern Europe and cryptic species 2 in northern or eastern Europe. However, the studied molecular markers did not reveal geographical patterns suggesting origins in different glacial refugia. Although populations of both cryptic species have decreased in large portions of western Europe, a significantly negative Tajima's D may reflect the long-term expansion south of Scandinavia since the glacial bottleneck, potentially correlated with the expansion of earlier extensive agricultural management of wetlands. [ABSTRACT FROM AUTHOR]

Cryptic species are rarer than their combined, morphologically recognisable species. Each cryptic species may have its own habitat requirements and distribution, and each should be considered separately in biodiversity conservation. This investigation explores how well the two cryptic species of the wetland moss Hamatocaulis vernicosus (Mitt.) Hedenäs s.l., included in Annex II of the EU Habitat Directive, are safeguarded in existing protected sites in Sweden. Further, the northern distribution limit of the southern of the two cryptic species is explored. The distributions of the two cryptic species and their intraspecific variation are judged by the nuclear ITS1 + 2 and the two chloroplast markers rpl16 and trnL-trnF for a set of 89 specimens. The genetic differences between the two cryptic species are significant, but there are no differences between the protected and non-protected subsets within the respective species. The protected areas therefore represent these two species’ genetic variation well. The populations of both cryptic species appear stable, according to their genetic signals. One of the two cryptic species occurs almost throughout Sweden, whereas the other occurs only to the south of the southern limit of the southern boreal zone, except for two finds slightly further north in climatically mild areas. [ABSTRACT FROM AUTHOR]