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1 Leaf blades reniform, as wide or wider than long, the base strongly cordate; staminodia shorter than the stamens [note that the stamens elongate after the staminodia; thus at a certain early stage the stamens of P. asarifolia may be shorter than the staminodia; check several flowers]; petal margins crisped
1 Leaf blades ovate, longer than wide, the base rounded, broadly cuneate, truncate, or cordate; staminodia longer than the stamens (P. caroliniana and P. grandifolia) or shorter than the stamens (P. glauca); petal margins planar.
..2 Staminodia shorter than the stamens; [NJ, PA, and OH northward]
..2 Staminodia longer than the stamens; [VA, WV, MO, OK southward].
....3 Main parallel veins of each petal (9-) 11-17 (counted at a point halfway between the base and the apex and ignoring short laterals), usually not dilated toward the apex of the petal; outer- or basal-most main vein branching pseudo-dichotomously several times; rhizome horizontal, long-creeping, the leaves scattered or loosely clustered, tending to form clonal patches to several m in diameter; ovary white; [Coastal Plain pinelands]
....3 Main parallel veins of each petal 5-9 (counted at a point halfway between the base and the apex and ignoring short laterals), often strongly dilated toward the apex of the petal; outer- or basal-most main vein with numerous short laterals on the outer side, extending to the petal margin with few or no branchings; rhizome erect, short, the leaves strongly clustered, not forming large clonal patches; ovary green, sometimes white toward the base; [primarily of the Mountains, rarely also disjunct in the Coastal Plain]