Phytotaxa 333 (1): 001–021 ISSN 1179-3155 (print edition) http://www.mapress.com/j/pt/ PHYTOTAXA Copyright © 2018 Magnolia Press Article ISSN 1179-3163 (online edition) https://doi.org/10.11646/phytotaxa.333.1.1 Sphagnum incundum a new species in Sphagnum subg. Acutifolia (Sphagnaceae) from boreal and arctic regions of North America MAGNI OLSEN KYRKJEEIDE*1, KRISTIAN HASSEL2, BLANKA SHAW3, A. JONATHAN SHAW3, EVA M. TEMSCH4 & KJELL IVAR FLATBERG2 1Norwegian Institute for Nature Research, N-7485 Trondheim, Norway 2NTNU University Museum, Norwegian University of Science and Technology, NO-7491 Trondheim, Norway 3Duke University, Department of Biology, Durham, North Carolina 27708 USA 4Department of Botany and Biodiversity Research, University of Vienna, Rennweg 14, Vienna, Austria *Corresponding author:
[email protected] Abstract We describe Sphagnum incundum in Sphagnum subg. 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 ex- amination 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).