Dryas alaskensis

A. E. Porsild

Canad. Field-Naturalist 61: 187, plate 1, figs. 3 – 5. 1948.

Common names: Alaskan mountain-avens
Synonyms: Dryas octopetala subsp. alaskensis (A. E. Porsild) Hultén D. octopetala var. glabrata Hultén D. punctata subsp. alaskensis (A. E. Porsild) Jurtzev
Treatment appears in FNA Volume 9. Treatment on page 329. Mentioned on page 328, 330.

Plants 2–18 cm. Leaf-blades obovate or oblongelliptic to narrowly oblong, 4.5–39 × 2–19 mm, base usually cuneate, sometimes truncate or cordate, margins coarsely dentate to crenate, sinuses 45–60% to midvein, apex rounded to obtuse, surfaces smooth to rugose, plicate, midvein and lateral-veins adaxially sunken into folds, abaxial sparsely hairy to tomentose, adaxial usually glabrous, sometimes sparsely hairy proximally on midvein, feathery hairs and stipitate-glands absent. Peduncles 25–130 mm. Flowers erect at flowering; sepals lanceolate to narrowly elliptic, 5.5–9 × 1.5–2 mm; petals 8, spreading, usually white or cream, sometimes yellow, 9–14 × 5–11 mm; filaments glabrous. Achenes 2–3 mm; styles 12–27 mm. 2n = 18.


Phenology: Flowering Jun–Aug.
Habitat: Solifluction soil, sand-gravel beaches, sandy lakeshores, old beach ridges, wet meadows, stream banks, dry rocky knolls, rocky heath, ericaceous tundra
Elevation: 100–1800 m

Distribution

V9 537-distribution-map.jpg

Yukon, Alaska, e Asia (Russian Far East: Chukotka)

Discussion

Dryas punctata Juzepczuk has been reported from North America as a synonym of D. octopetala var. octopetala (E. Hultén 1968); it is now considered to be confined to northeastern Europe and northern Asia (R. Elven et al., http://nhm2.uio.no/paf/). Hultén (1959b) reduced D. octopetala var. glabrata to the rank of forma and later to synonymy under D. alaskensis (Hultén 1968).

Selected References

None.

Lower Taxa

None.
... more about "Dryas alaskensis"
sparsely hairy +  and tomentose +
hairy +  and glabrous +
Joshua C. Springer +  and Bruce D. Parfitt† +
A. E. Porsild +
blackish +, reddish +  and brown +
compound +  and simple +
opposite +  and alternate +
cordate +, truncate +  and cuneate +
3.9 cm39 mm <br />0.039 m <br /> (4.6 cm46 mm <br />0.046 m <br />) +
smooth +  and rugose +
ovate +, oval +, obovate +, oblongelliptic +, oblong +, linear +, lanceolate +  and elliptic +
0.2 cm2 mm <br />0.002 m <br /> (3.9 cm39 mm <br />0.039 m <br />) +
stoloniferous +
free +  and distinct +
Alaskan mountain-avens +
Yukon +, Alaska +  and e Asia (Russian Far East: Chukotka) +
not +  and aggregated +
100–1800 m +
stipitate-glandular +  and villous +
1.3 cm13 mm <br />0.013 m <br /> (2.9 cm29 mm <br />0.029 m <br />) +
unisexual +  and bisexual +
not +  and aggregated +
linear +  and lanceolate +
0.08 cm0.8 mm <br />8.0e-4 m <br /> (0.35 cm3.5 mm <br />0.0035 m <br />) +
Solifluction soil, sand-gravel beaches, sandy lakeshores, old beach ridges, wet meadows, stream banks, dry rocky knolls, rocky heath, ericaceous tundra +
0.3 cm3 mm <br />0.003 m <br /> (1.5 cm15 mm <br />0.015 m <br />) +
crassinucellate +
0.45 cm4.5 mm <br />0.0045 m <br /> (3.9 cm39 mm <br />0.039 m <br />) +
0.2 cm2 mm <br />0.002 m <br /> (1.9 cm19 mm <br />0.019 m <br />) +
persistent +
entire +, serrate +  and dentate +
coarsely dentate +  and crenate +
inferior +  and superior +
clustered +, biseriate +  and superposed +
2.5 cm25 mm <br />0.025 m <br /> (13 cm130 mm <br />0.13 m <br />) +
Yellow (?) +, Cream (?) +  and White (?) +
persistent +  and deciduous +
free +  and distinct +
0.9 cm9 mm <br />0.009 m <br /> (1.4 cm14 mm <br />0.014 m <br />) +
0.5 cm5 mm <br />0.005 m <br /> (1.1 cm11 mm <br />0.011 m <br />) +
Flowering Jun–Aug. +
adnate +, free +, connate +  and distinct +
Canad. Field-Naturalist +
not arillate +
persistent +
free +  and distinct +
erect-ascending +, ascending +  and spreading +
lanceolate +  and narrowly elliptic +
0.15 cm1.5 mm <br />0.0015 m <br /> (0.2 cm2 mm <br />0.002 m <br />) +
free +  and distinct +
rooting +  and branched +
adnate +  and free +
persistent +
distinct +
basal +, lateral +, subterminal +  and terminal +
elongate +
1.2 cm12 mm <br />0.012 m <br /> (2.7 cm27 mm <br />0.027 m <br />) +
smooth +  and rugose +
Dryas octopetala subsp. alaskensis +, D. octopetala var. glabrata +  and D. punctata subsp. alaskensis +
Dryas alaskensis +
species +
inconspicuous +
hemispheric +