Abstract
We describe Sphagnum incundum in Sphagnum subgenus Acutifolia (Sphagnaceae, Bryophyta). We used both molecular and morphological methods to describe the new species. Molecular relationships with closely related species were explored based on microsatellites and nuclear and plastid DNA sequences. The morphological description is based on qualitative examination of morphological characters and measurements of leaves and hyalocysts. Morphological characters are compared between closely related species. The results from Feulgen densitometry and microsatellite analysis show that S. incundum is gametophytically haploid. Molecular analyses show that it is a close relative to S. flavicomans, S. subfulvum and S. subnitens, but differs both genetically and in morphological key characters, justifying the description of S. incundum as a new species. The new peatmoss is found in North America along the western coast of Greenland, in Canada from Quebec and Northwest Territories, and Alaska (United States). The new species has a boreal to arctic distribution.
