Flora of North America species comparison

never tuberous.

erect or ascending, never rooting nodally, crisped-pilose, base not bulbous.

creeping or floating, rooting nodally, glabrous, not bulbous-based.

broadly rhombic to semicircular in outline, 3-parted, 2.8-4.3 × 3-5.5 cm, segments 3-lobed, ultimate segments lanceolate, margins entire or toothed, apex narrowly acute or acuminate.

linear to obovate, undivided or 3-lobed, 1.5-3.6 × 0.3-2 cm, lobes lanceolate or elliptic, margins entire, apex rounded to acuminate.

receptacle glabrous;

sepals reflexed 1 mm above base, 4-6 × 1.5-3 mm, densely pilose;

petals 5, abaxially red, adaxially yellow, 10-12 × 4-6 mm.

receptacle glabrous;

sepals spreading, 6-10 × 4-7 mm, glabrous;

petals 7-11, white or pink, 8-13 × 3-6 mm.

of achenes hemispheric, 4-7 × 7-10 mm;

achenes 3.4-4.2 × 2.8-3.2 mm, sometimes basally pilose, margin forming narrow rib 0.1-0.2 mm wide;

beak persistent, lance-subulate, straight or somewhat curved distally, 1.6-2.6 mm.

of achenes globose or hemispheric, 5-12 × 9-15 mm;

achenes 4.2-5.2 × 2.4-3.2 mm, glabrous;

beak persistent, lanceolate, straight or curved, 1-1.2 mm.

roots absent.

= 32.