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

Rhizomes

3-8 cm diam.

ca. 7-8 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 and adaxially green, often suffused with purple, orbiculate or nearly so, 20-45 × 20-45 cm, 1-1.2 times as long as wide, sinus ca. 1/2 length of midrib, lobes approximate to overlapping;

surfaces abaxially 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.

4-8 cm diam.;

sepals 6, abaxially green to adaxially yellow, never red-tinged toward base;

petals oblong, thick;

anthers 5-6 mm, longer 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.

greenish or yellowish, cylindric to nearly globose, 3.5-5 cm, smooth basally, finely ribbed toward apex, slightly constricted below stigmatic disk;

stigmatic disk green, yellow, or sometimes reddened, ca. 30-35 mm diam., undulate;

stigmatic rays 12-28, linear or lanceolate, terminating 1-3 mm from margin of disk.

Seeds

3.5-5 mm.

4-6 mm.

2n

= 34.

Nuphar polysepala

Nuphar orbiculata

Phenology Flowering spring (later in north)-summer. Flowering mid spring–early fall.
Habitat Ponds, lakes, and sluggish streams Acidic ponds
Elevation 0-3700 m (0-12100 ft) 0-100 m (0-300 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
AL; FL; GA
Discussion

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

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

Nuphar orbiculata is perhaps best treated as a subspecies. Plants intermediate between it and N. advena occur in southern Georgia and northern Florida.

(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. microphylla, N. polysepala, N. rubrodisca, N. sagittifolia, N. ulvacea, N. variegata
Synonyms N. lutea subsp. polysepala, Nymphaea polysepala Nymphaea orbiculata, N. lutea subsp. orbiculata, Nymphaea bombycina
Name authority Engelmann: Trans. Acad. Sci. St. Louis 2: 282. 1865 (as polysepalum) (Small) Standley: Publ. Field Columbian Mus., Bot. Ser. 8: 311. 1931 (as orbiculatum)
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