Niphotrichum sect. Elongata

Plants small, medium-sized to robust, green, olive or grayish green distally, brown. Leaves ovate-lanceolate, lanceolate to triangular, sharply keeled to narrowly canaliculate in the distal part; costa in most leaves unbranched or only occasionally forked in some leaves, extending to three quarters of the leaf length to percurrent; leaf cell papillae tending to be relatively small and inconspicuous in the distal lamina.

Distribution

North America, Europe, temperate Asia, Atlantic Islands.

Discussion

Species 6 (4 in the flora).

Section Elongata is fairly homogeneous. Its members are readily recognized by their leaves, which are sharply keeled to narrowly canaliculate or canaliculate-keeled in the distal part, and their costae, which cease mostly at three quarters of the leaf length or are subpercurrent to percurrent and are generally undivided at the tip.

Selected References

None.

Lower Taxa

Niphotrichum elongatum, Niphotrichum ericoides, Niphotrichum muticum, Niphotrichum pygmaeum

Key

1	Leaf margins recurved to 1/2-3/4 of the way up the leaf.	Niphotrichum muticum
1	Leaf margins recurved to the apex	> 2
2	Plants small; leaves 1.5-1.8 mm long; costa not grooved; laminal cells opaque, coarsely papillose, yellowish; alar cells forming a small and weakly inflated group; awns absent papillae or only faintly papillose at the base	Niphotrichum pygmaeum
2	Plants medium-sized to large; leaves 2-3 mm long; costa lying in a shallow or deeper furrow; laminal cells coarsely to slightly papillose, mostly transparent, not yellowish (except the base); alar cells forming a conspicuous and distinctly inflated group; awns mostly coarsely papillose	> 3
3	Supra-alar cells elongate, thin-walled and not sinuose, forming a transparent marginal border; awns erect-flexuose when dry, not or indistinctly decurrent, faintly papillose to epapillose in the distal part	Niphotrichum ericoides
3	Supra-alar cells short, thick- and sinuose-walled, not forming a translucent border; awns recurved when dry, conspicuously decurrent, coarsely papillose throughout.	Niphotrichum elongatum