7a. Niphotrichum (Bednarek-Ochyra) Bednarek-Ochyra & Ochyra sect. Niphotrichum
Racomitrium [unranked] Canescentia Kindberg; Racomitrium sect. Canescentia (Kindberg) Bednarek-Ochyra
Plants medium-sized to robust, green, olive or grayish green distally, brown to blackish proximally. Leaves elliptical, ovate to ovate-lanceolate, broadly canaliculate to obtusely keeled in the distal part; costa distinctly branched or forked in most leaves, extending to mid leaf or three quarters of the leaf length; leaf cell papillae comparatively large and conspicuous in the distal part of the lamina.
Species 2 (2 in the flora): North America, Europe, arctic and temperate Asia, Atlantic Islands (Iceland).
Section Niphotrichum is best characterized by fairly short costae that usually extend to 1/2-3/4 of the way up the leaf and often imperceptibly merge with the laminal cells. This results in the shape of the distal parts of the leaves, which are broadly canaliculate to obtusely carinate in profile as clearly seen in transverse sections. In addition, the costae are distinctly branched or forked at the apex in most leaves.
SELECTED REFERENCE
Frisvoll, A. A. 1983. A taxonomic revision of the Racomitrium canescens group (Bryophyta, Grimmiales). Gunneria 41: 1-181.
