Flora of North America species comparison

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

reclining or erect, glabrous or sparsely pilose.

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 spreading, 6-10 × 4-7 mm, glabrous;

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

pedicellate;

receptacle hispid;

sepals 5, reflexed, 4-7 × 2-3 mm, sparsely bristly;

petals 5, 4-8 × 2-4.5 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.

globose, 13-16 × 13-16 mm;

achenes 10-20 per head, 5-5.5 × 3-3.5 mm, faces covered with long spines, glabrous, margin smooth;

beak lanceolate, curved, 2-2.5 mm.

roots absent.

and lower cauline leaf blades broadly cordate to reniform or semicircular, undivided or 3-lobed, 2-5 × 3-6.5 cm, base rounded to cordate, margins coarsely crenate, apex rounded.

= 32.