Conservation status of the two cryptic species of Hamatocaulis vernicosus (Bryophyta) in Sweden

Abstract

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.

Keywords:

• Boreal zone
• Diversity
• EU Habitat Directive
• Molecular markers
• Phylogeography
• Wetland

Acknowledgements

I thank L. Appelgren, P. Darell, U. Gunnarsson, M. Hagström, N. Lönnell, T. Pettersson, and T. Troschke for providing material to this study, and W. Solis for her efficient laboratory work at the Centre for Genetic Identification at the Swedish Museum of Natural History. Comments on drafts of the text by N. Lönnell and K. Wiklund are appreciated. Two anonymous reviewers and A. Vanderpoorten provided valuable input on the manuscript. This work was supported by Naturvårdsverket through Länsstyrelsen i Uppsala län (dnr. 511-4800-2017).

Taxonomic Additions and Changes: Nil.

ORCID

Lars Hedenäs http://orcid.org/0000-0003-1763-1696