Potentilla hyparctica

Malte

Rhodora 36: 177. 1934.

Common names: Arctic cinquefoil
Illustrated
Synonyms: Potentilla robbinsiana subsp. hyparctica (Malte) D. Löve
Treatment appears in FNA Volume 9. Treatment on page 192. Mentioned on page 147, 187, 189, 190, 201, 212, 218.

Plants cushion-forming; caudex branches short-to-elongate, slender, often embedded in old leaf-bases. Stems ascending to erect, 0.2–2 (–2.5) dm, lengths 1–3 (–4) times basal leaves. Basal leaves not in ranks, ternate, (1–) 2–8 (–10) cm; stipules: apex ± acute; petiole 1–6.5 (–8.5) cm, long hairs sparse to common, spreading to subappressed, 0.8–2 mm, weak to ± stiff, glands sparse to common; leaflets 3, central obovate to broadly obovate, 0.5–2.5 (–2.8) × 0.3–2 (–2.2) cm, petiolule 0–3 mm, margins flat or slightly revolute, not lobed, distal 1/2–2/3 (–3/4) evenly incised ± 1/2 to midvein, teeth (2–) 3–5 per side, surfaces ± similar, abaxial usually pale green, sometimes grayish, hairs sparse to abundant, 0.5–1.7 mm, adaxial darker green, hairs and glands sparse. Inflorescences 1–3 (–5) -flowered. Pedicels straight, 0.3–3 cm in flower, to 9 cm in fruit. Flowers: epicalyx bractlets narrowly to broadly oblong or ovate, 3.5–7 × 1.5–5 mm, margins flat; hypanthium 4–7 mm diam.; sepals 4–8 mm, apex subacute to rounded; petals pale or bright-yellow, 4–9 × 4–6 mm; filaments 0.5–1.1 mm, anthers 0.2–0.4 mm; carpels 50–80, styles ± columnar, not or scarcely papillate-swollen proximally, 0.6–0.9 mm. Achenes 1.1–1.3 mm.

Distribution

V9 291-distribution-map.jpg

Alta., B.C., N.W.T., Nfld. and Labr., Nunavut, Que., Yukon, Alaska, Mont., Wash., Wyo., n Eurasia, circumpolar

Discussion

Subspecies 3 (2 in the flora).

Southern arctic and subarctic plants differ from the northern arctic ones in presumably independent features. Where the two forms are sympatric (western Greenland, northern Quebec, Baffin Island), they appear to remain distinct even in mixed populations and are accordingly treated as subspecies.

Although some features of scattered plants in Alaska and Yukon approach subsp. nivicola Jurtzev & V. V. Petrovsky (described from northeastern Asia), such plants do not otherwise correspond fully with this taxon. Possible hybrids between Potentilla hyparctica and P. pulchella (sect. Pensylvanicae) are addressed in the discussion of sect. Pensylvanicae. Presumed hybrids with P. villosa from the Aleutian Islands, characterized by the combination of basally thickened styles and lack of cottony hairs on leaflet abaxial surfaces, have been named P. ×aleutica Soják.

Selected References

None.

Key

1 Epicalyx bractlets narrowly to ± oblong or ovate, 1.5–2 mm wide; central leaflets: petiolules 0–2 mm, bases cuneate. Potentilla hyparctica subsp. hyparctica
1 Epicalyx bractlets broadly oblong or ovate, 2–5 mm wide; central leaflets: petiolules (0–)2–3(–5) mm, bases broadly cuneate to rounded. Potentilla hyparctica subsp. elatior

"dm" is not declared as a valid unit of measurement for this property.

... more about "Potentilla hyparctica"
grayish +  and pale green +
pale +  and dark green rarely grayish brownish or reddish +
1.1mm +  and 1.3mm +
green +  and dark green rarely brownish or reddish +
0.02 cm0.2 mm <br />2.0e-4 m <br /> (0.04 cm0.4 mm <br />4.0e-4 m <br />) +
Reidar Elven +, Barbara Ertter +, David F. Murray +  and James L. Reveal +
8 cm80 mm <br />0.08 m <br /> (10 cm100 mm <br />0.1 m <br />) +
2 cm20 mm <br />0.02 m <br /> (8 cm80 mm <br />0.08 m <br />) +
Aureae +
25 cm250 mm <br />0.25 m <br /> (30 cm300 mm <br />0.3 m <br />) +
less cordate or reniform +  and narrowly elliptic +
0.5 cm5 mm <br />0.005 m <br /> (25 cm250 mm <br />0.25 m <br />) +
reduced +
free +  and distinct +
hairy +  and glabrous +
slender +, short +  and elongate +
2.5 cm25 mm <br />0.025 m <br /> (2.8 cm28 mm <br />0.028 m <br />) +
2 cm20 mm <br />0.02 m <br /> (2.2 cm22 mm <br />0.022 m <br />) +
0.5 cm5 mm <br />0.005 m <br /> (2.5 cm25 mm <br />0.025 m <br />) +
obovate +  and broadly obovate +
0.3 cm3 mm <br />0.003 m <br /> (2 cm20 mm <br />0.02 m <br />) +
Arctic cinquefoil +
Alta. +, B.C. +, N.W.T. +, Nfld. and Labr. +, Nunavut +, Que. +, Yukon +, Alaska +, Mont. +, Wash. +, Wyo. +, n Eurasia +  and circumpolar +
not +  and aggregated +
0.35 cm3.5 mm <br />0.0035 m <br /> (0.7 cm7 mm <br />0.007 m <br />) +
ovate +  and oblong +
0.15 cm1.5 mm <br />0.0015 m <br /> (0.5 cm5 mm <br />0.005 m <br />) +
0.05 cm0.5 mm <br />5.0e-4 m <br /> (0.11 cm1.1 mm <br />0.0011 m <br />) +
5-merous +, solitary +  and open +
0.8 cm8 mm <br />0.008 m <br /> (2 cm20 mm <br />0.02 m <br />) +
unisexual +  and bisexual +
not +  and aggregated +
deciduous +
on style scar +, hairy +  and glabrous +
0.05 cm0.5 mm <br />5.0e-4 m <br /> (0.26 cm2.6 mm <br />0.0026 m <br />) +
stoloniferous +  and short-rhizomatous +
straight +
weak +  and more or less stiff +
spreading +  and subappressed +
sparse +  and abundant +
crisped +
0.05 cm0.5 mm <br />5.0e-4 m <br /> (0.17 cm1.7 mm <br />0.0017 m <br />) +
not differentiated +
0.25 cm2.5 mm <br />0.0025 m <br /> (0.5 cm5 mm <br />0.005 m <br />) +
0.7 cm7 mm <br />0.007 m <br /> (1 cm10 mm <br />0.01 m <br />) +
0.4 cm4 mm <br />0.004 m <br /> (0.7 cm7 mm <br />0.007 m <br />) +
0.05 cm0.5 mm <br />5.0e-4 m <br /> (0.25 cm2.5 mm <br />0.0025 m <br />) +
0.2 cm2 mm <br />0.002 m <br /> (0.7 cm7 mm <br />0.007 m <br />) +
crassinucellate +
bipinnate +, odd-pinnate +, subpalmate +, palmate +  and ternate +
opposite +  and alternate +
marcescent +
well-developed +
persistent +
cauline +  and basal +
reduced +
not +  and overlapping +
obtriangular +  and flabellate +
linear +  and oblanceolate +
palmate +  and pinnate +
1/2 +  and 2/3-3/4 +
incised +, not lobed +, revolute +  and flat +
inferior +  and superior +
clustered +, biseriate +  and superposed +
3 cm30 mm <br />0.03 m <br /> (9 cm90 mm <br />0.09 m <br />) +
0 cm0 mm <br />0 m <br /> (9 cm90 mm <br />0.09 m <br />) +
1 cm10 mm <br />0.01 m <br /> (1.2 cm12 mm <br />0.012 m <br />) +
free +  and distinct +
0.4 cm4 mm <br />0.004 m <br /> (0.9 cm9 mm <br />0.009 m <br />) +
usually longer +
0.3 cm3 mm <br />0.003 m <br /> (1 cm10 mm <br />0.01 m <br />) +
0.4 cm4 mm <br />0.004 m <br /> (0.6 cm6 mm <br />0.006 m <br />) +
6.5 cm65 mm <br />0.065 m <br /> (8.5 cm85 mm <br />0.085 m <br />) +
1 cm10 mm <br />0.01 m <br /> (6.5 cm65 mm <br />0.065 m <br />) +
0 cm0 mm <br />0 m <br /> (0.3 cm3 mm <br />0.003 m <br />) +
adnate +, free +, connate +  and distinct +
palmate +  and ternate +
12 cm120 mm <br />0.12 m <br /> (20 cm200 mm <br />0.2 m <br />) +
1 cm10 mm <br />0.01 m <br /> (12 cm120 mm <br />0.12 m <br />) +
usually not much longer +
not arillate +
persistent +
free +  and distinct +
erect +  and spreading +
lanceolate +  and broadly ovate or deltate +
0.4 cm4 mm <br />0.004 m <br /> (0.8 cm8 mm <br />0.008 m <br />) +
Illustrated +
free +  and distinct +
not rooting +
reddish +  and green +
1-3(-4) times basal leaves +
ascending +  and erect +
1 +  and many +
not flagelliform +
palmate +  and pinnate +
deciduous +
distinct +
subapical +
papillate-swollen +  and columnar +
rough-thickened +
0.06 cm0.6 mm <br />6.0e-4 m <br /> (0.09 cm0.9 mm <br />9.0e-4 m <br />) +
Potentilla robbinsiana subsp. hyparctica +
not fleshy-thickened +
Potentilla hyparctica +
Potentilla sect. Aureae +
species +
3 +  and 5 +
inconspicuous +
enlarged +
matted +  and cushion-forming +
biennial +, annual +  and perennial +
plant +  and cushion-forming +