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Rocky Mountain cowlily, Rocky Mountain pond-lily, spatterdock, wakas, yellow pond-lily

petit nénuphar jaune, small-leaf pond-lily, yellow pond-lily

Rhizomes

3-8 cm diam.

1-2 cm diam.

Leaves

blade abaxially and adaxially green, widely ovate, 10-40(-45) × 7-30 cm, ca. 1.2-1.5 times as long as wide, sinus 1/3-2/3 length of midrib, lobes divergent to overlapping;

surfaces glabrous.

blade abaxially often purple, adaxially green to greenish purple, broadly elliptic to ovate, 3.5-10(-13) × 3.5-7.5(-8.5) cm, 1-1.5 times as long as wide, sinus 2/3 or more length of midrib, lobes divergent and forming V-shaped angle;

surfaces abaxially glabrous to densely pubescent.

Flowers

5-10 cm diam.;

sepals mostly (6-)9(-12), abaxially green to adaxially yellow, sometimes red-tinged toward base;

petals oblong, thick;

anthers 3.5-9 mm, slightly shorter than filaments.

1-2 cm diam.;

sepals 5(-10), abaxially green to adaxially yellow toward base;

petals broadly spatulate and thin, or notched and thickened;

anthers 1-3 mm, shorter than filaments.

Fruit

green to yellow, cylindric to ovoid, 4-6(-9) × 3.5-6 cm, strongly ribbed, slightly constricted below stigmatic disk;

stigmatic disk green, 20-35 mm diam., entire to crenate;

stigmatic rays 8-26(-36), linear to lanceolate, terminating within 1(-1.5) mm from margin of disk.

yellow, green, brown, or rarely purple, mostly globose-ovoid, occasionally flask-shaped, 1-2 cm, smooth basally, faintly ribbed toward apex, deeply constricted below stigmatic disk, constriction 1.5-5 mm diam.;

stigmatic disk red, 2.5-7 mm diam., with 6-10 deep crenations;

stigmatic rays 6-11, linear, terminating 0-0.2 mm from margin of disk.

Seeds

3.5-5 mm.

ca. 3 mm.

2n

= 34.

= 34.

Nuphar polysepala

Nuphar microphylla

Phenology Flowering spring (later in north)-summer. Flowering summer–early fall.
Habitat Ponds, lakes, and sluggish streams Ponds, lakes, sluggish streams, sloughs, ditches, and occasionally tidal waters
Elevation 0-3700 m (0-12100 ft) 0-400 m (0-1300 ft)
Distribution
from FNA
AK; AZ; CA; CO; ID; MT; NM; NV; OR; UT; WA; WY; BC; NT; YT
[WildflowerSearch map]
[BONAP county map]
from FNA
CT; MA; ME; MI; MN; NH; NJ; NY; PA; VT; WI; MB; NB; NS; ON; QC; Europe; n Asia
[WildflowerSearch map]
[BONAP county map]
Discussion

Plants intermediate between Nuphar polysepala and N. variegata occur in eastern British Columbia.

(Discussion copyrighted by Flora of North America; reprinted with permission.)

Intermediates between Nuphar microphylla and N. variegata, probably of hybrid origin, are treated as N. rubrodisca. A form with ten sepals (Nuphar microphyllum forma multisepalum Lakela) occurs in northeastern Minnesota. Recent observations of the Eurasian N. pumila (Timm) de Candolle by C. B. Hellquist in Siberia suggest that Beal's lumping of N microphylla under N. lutea subsp. pumila (Timm) E. O. Beal should be further studied.

(Discussion copyrighted by Flora of North America; reprinted with permission.)

Source FNA vol. 3. FNA vol. 3.
Parent taxa Nymphaeaceae > Nuphar Nymphaeaceae > Nuphar
Sibling taxa
N. advena, N. microphylla, N. orbiculata, N. rubrodisca, N. sagittifolia, N. ulvacea, N. variegata
N. advena, N. orbiculata, N. polysepala, N. rubrodisca, N. sagittifolia, N. ulvacea, N. variegata
Synonyms N. lutea subsp. polysepala, Nymphaea polysepala Nymphaea microphylla, N. kalmiana, N. minima
Name authority Engelmann: Trans. Acad. Sci. St. Louis 2: 282. 1865 (as polysepalum) (Persoon) Fernald: Rhodora 19: 111. 1917 (as microphyllum)
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