Polytrichastrum alpinum var. fragile

(Bryhn) D. G. Long

Meddel. Grønland, Biosci. 17: 30. 1985,.

Basionym: Polytrichum fragile Bryhn Bryoph. Itin. Pol. Norv., 122, plate 122, fig. 3. 1906
Synonyms: Pogonatum alpinum var. fragile (Bryhn) H. A. Crum Polytrichum alpinum var. fragile (Bryhn) Nyholm
Treatment appears in FNA Volume 27. Treatment on page 128. Mentioned on page 125, 126.

Stems 1–2 cm, in compact tufts. Leaves fragile, constricted at the junction of sheath and blade, the blade caducous; marginal lamina entire, rarely distantly serrulate. Capsule ovoid or subglobose.


Habitat: Growing where subject to periodic inundation, wet meadows, springs and lake margins, occasional in open tundra, beach ridges and roadside banks, low elevations

Distribution

V27 151-distribution-map.gif

Greenland, N.W.T., Nunavut, Alaska, Europe (n Scandinavia), Asia (Russia in Siberia)

Discussion

Variety fragile is a distinctive taxon of the high Arctic with regularly caducous leaves, in North America common only in arctic Alaska on the coastal plain to 100(–800) m, with scattered records throughout arctic Canada (D. G. Long 1985). In Nunavut, it is known from Baffin Island, Ellesmere Island, and Melville Island.

Selected References

None.

Lower Taxa

None.

"broadened" is not a number."wide" is not a number.

narrowly acute;finely acuminate +
prominent +
Gary L. Smith Merrill +
(Bryhn) D. G. Long +
toothed +
differentiated +
Polytrichum fragile +
distinct +
linear-lanceolate +
firm-textured +
entire +  and serrate +
not pitted +  and papillose +
monoicous +, dioicous +, sexual +  and vegetative +
distantly serrulate;subentire +
sparsely ciliate;smooth +
cucullate +
0.5 cm5 mm <br />0.005 m <br /> (0.8 cm8 mm <br />0.008 m <br />) +
horizontal;suberect;inclined +
subglobose +  and ovoid +
0.3 cm3 mm <br />0.003 m <br /> (0.5 cm5 mm <br />0.005 m <br />) +
prolonged +
toothed +
undifferentiated +
Greenland +, N.W.T. +, Nunavut +, Alaska +, Europe (n Scandinavia) +  and Asia (Russia in Siberia) +
scabrous +, mammillose +  and smooth +
Growing where subject to periodic inundation, wet meadows, springs and lake margins, occasional in open tundra, beach ridges and roadside banks, low elevations +
photosynthetic +
5 +  and 8 +
serrate +, crenulate +  and serrulate +
elongate +  and subquadrate +
0.8 cm8 mm <br />0.008 m <br /> (1.9 cm19 mm <br />0.019 m <br />) +
erect-spreading +  and widely spreading +
constricted +
0.5 cm5 mm <br />0.005 m <br /> (0.8 cm8 mm <br />0.008 m <br />) +
membranous +
papillose +
pointed +  and pentagonal +
1(-3)-stratose +
papillose +  and smooth +
crenulate +  and serrulate +
shape +  and size +
polygamous +, dioicous +  and sexual +
ovate;narrowly ovate +
sharply toothed +  and entire +
interwoven +
600 cm6,000 mm <br />6 m <br /> (?) +
toothlike +
Meddel. Grønland, Biosci. +
underground +
undifferentiated +
enlarged +
1 cm10 mm <br />0.01 m <br /> (3 cm30 mm <br />0.03 m <br />) +
3 cm30 mm <br />0.03 m <br /> (5 cm50 mm <br />0.05 m <br />) +
hyaline-margined +
elongate-rectangular +
elliptic;obovate +
differentiated +
larger +  and minute +
thick-walled +
branched +, simple or +  and sparingly fasciculately +
6 cm60 mm <br />0.06 m <br /> (14 cm140 mm <br />0.14 m <br />) +
thread-like +
1 cm10 mm <br />0.01 m <br /> (2 cm20 mm <br />0.02 m <br />) +
conspicuous +
Pogonatum alpinum var. fragile +  and Polytrichum alpinum var. fragile +
Polytrichastrum alpinum var. fragile +
Polytrichastrum alpinum +
variety +
multicellular +
darker +  and pale to somewhat +
unjointed +
not keeled +
unequal +
compact +  and loose +
reddish +, brownish green +, green +  and dull +
small +  and variable +