Flora of North America species comparison

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

erect or ascending from caudices, not rooting nodally, distally glabrous or brown-pilose, not bulbous-based.

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.

reniform to broadly triangular in outline, 3-foliolate or deeply 3-parted, 1-4 × 1.6-4.4 cm, leaflets or segments 1-2x-parted, ultimate segments elliptic to oblanceolate or almost linear, margins entire or occasionally with 1-2 teeth, apex rounded to obtuse.

receptacle glabrous;

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

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

receptacle glabrous or brown-pilose;

sepals spreading, 7-12 × 4-9 mm, brown-pilose;

petals initially white, usually becoming red with age, 9-15 × 7-14(-18) mm.

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.

roots absent.

heads hemispheric, 5-8 × 7-16 mm;

fruit wall smooth, not veined, loose but not inflated, winged along suture, fruits winged achenes;

achenes 2.6-3 × 1.4-2 mm, glabrous;

beak persistent, lanceolate, 0.8-2.3 mm.

= 32.