Niphotrichum canescens subsp. latifolium

(C. E. O. Jensen) Frisvoll

Gunneria 41: 123. 1983,.

Basionym: Racomitrium canescens var. latifolium C. E. O. Jensen Meddel. Grønland 3(2): 345. 1887
Treatment appears in FNA Volume 27. Treatment on page 288. Mentioned on page 287.

Plants fairly gracile. Leaves ovatelanceolate, straight or occasionally weakly falcate, often less obtusely keeled distally, chlorophyllous at the apex; awns mostly subulate and flexuose, distinctly decurrent, moderately denticulate and spinulose towards the extreme apex.


Habitat: Dry to moist, exposed habitats, acidic or less often calciferous substrates, soil, humus, rock-debris and rocky ground, between boulders, talus slopes, cliffs and ledges various communities of polar tundra and tundra-like alpine heaths and barrens
Elevation: low to high elevations (0-2000 m)

Distribution

V27 395-distribution-map.gif

Greenland, Alta., B.C., N.W.T., Nunavut, Que., Yukon, Alaska, Wash., Europe (Jan Mayen), Europe (Spitsbergen), Europe (Fennoscandia), arctic and temperate Asia (Japan), arctic and temperate Asia (Sikkim), Atlantic Islands (Iceland)

Discussion

Subspecies latifolium is widely distributed from Alaska to Greenland. The ranges of both subspecies overlap in the Rocky Mountains of British Columbia and Washington, and there the differences between the taxa seem to be less pronounced. There are some problematic plants with narrower awns and more lanceolate leaves, but because they are robust and have falcate leaves, they are referred to subsp. canescens. The plants from the more northerly regions are easy to determine. They are slender and the leaves are ovate-lanceolate, less concave, mostly straight, and chlorophyllose at the apex. Consequently, the awns embrace only the small uppermost part of the leaf lamina and are long-decurrent. In the Arctic, subsp. latifolium is likely to be mistaken for N. panschii. The differences between these taxa are discussed under the next species.

Selected References

None.

Lower Taxa

None.
not +  and hyaline +
inflated +  and decurrent +
Ryszard Ochyra +  and Halina Bednarek-Ochyra +
(C. E. O. Jensen) Frisvoll +
capillaceous +
flexuose +
not reflexed +
papillose +
denticulate +, decurrent +  and subulate +
nodulose;oblate;quadrate;elongate +
rectangular +
divided +
Racomitrium canescens var. latifolium +
2;3;2;numerous +
papillose +
linear-subulate +  and tuft-like +
undifferentiated +
naked +, plicate +  and smooth +
lobed +, lacerated +, mitrate-campanulate +, mitrate +  and cucullate +
small;large +
furrowed +  and smooth to somewhat +
narrowly ellipsoid;cylindric +
0.15 cm1.5 mm <br />0.0015 m <br /> (0.25 cm2.5 mm <br />0.0025 m <br />) +
straight-walled +  and thin-walled +
hyaline +  and yellowish hyaline +
20 (?) +  and 30 (?) +
elongate +, inflated +  and rounded +
enlarged +
subpercurrent +
1/2 +  and 3/4 +
convex +  and flattened +
90um +  and 120um +
Greenland +, Alta. +, B.C. +, N.W.T. +, Nunavut +, Que. +, Yukon +, Alaska +, Wash. +, Europe (Jan Mayen) +, Europe (Spitsbergen) +, Europe (Fennoscandia) +, arctic and temperate Asia (Japan) +, arctic and temperate Asia (Sikkim) +  and Atlantic Islands (Iceland) +
low to high elevations (0-2000 m) +
Dry to moist, exposed habitats, acidic or less often calciferous substrates, soil, humus, rock-debris and rocky ground, between boulders, talus slopes, cliffs and ledges various communities of polar tundra and tundra-like alpine heaths and barrens +
chlorophyllous +
0.28 cm2.8 mm <br />0.0028 m <br /> (0.33 cm3.3 mm <br />0.0033 m <br />) +
thick-walled +  and sinuose +
straight +
2mm;2.8mm +
keeled +, falcate +  and ovatelanceolate +
0.08 cm0.8 mm <br />8.0e-4 m <br /> (0.13 cm1.3 mm <br />0.0013 m <br />) +
muticous +, acute +  and rounded-obtuse +
long-subulate +
piliferous;obtuse;acute +
cribrose +  and perforated +
lanceolate;linear +
dark red +  and reddish-brown +
sinistrorse +  and erect +
papillose +  and smooth +
short to long +
0.5 cm5 mm <br />0.005 m <br /> (2.5 cm25 mm <br />0.025 m <br />) +
ornamented +  and smooth +
globose +
3 cm30 mm <br />0.03 m <br /> (10 cm100 mm <br />0.1 m <br />) +
Bryum canescens +, Grimmia canescens +  and Racomitrium canescens +
Niphotrichum canescens subsp. latifolium +
Niphotrichum canescens +
subspecies +
divided +
yellowbrown;yellow-green;green;dull +
fairly slender;large +