1 Leaves with a slightly to strongly concave section at the transition from the basal lobes to the terminal portion of the leaf; leaves alternate, opposite, or a mixture of alternate and opposite.

  2 Leaf apex mucronate or acuminate; leaf lateral lobe apices rounded; petiole base not clasping; leaves 3-9 cm wide

  2 Leaf apex caudate; leaf lateral lobe apices acuminate; petiole base clasping; leaves 7-42 cm wide

1 Leaves with continuously convex lateral margins (except just below the acute to acuminate leaf apex) or with slight undulations of straight to very slightly concave sections.

    3 Aerial tubers never present; perennial from rhizomes < 1.5 cm in diameter; leaves whorled, alternate, or a mixture of whorled and alternate; [native species, usually of forests and woodlands]; [section Macropoda].

      4 Leaves with 7 main veins; staminate inflorescences usually of 1 large and 1-2 smaller secondary panicles in each axil (of upper stem leaves); filaments inwardly curved, ca. 0.4 mm long; anther lobes connate; tepals oblong; leaf margins often with subtle, very broad lobes, the margin thus with straight or very slightly concave segments; [of SC south]

      4 Leaves with 9 or more main veins; staminate inflorescence a single panicle in each axil (of median or upper leaves); filaments straight, ca. 0.2 mm long; anther lobes separate; tepals ovate; leaf margins convex; [widespread in our area]

    3 Aerial tubers present; perennial from large, vertically-oriented tubers; leaves alternate, or a mixture of alternate and opposite; [non-native species, usually in disturbed areas, especially in bottomlands]; [section Enantiophyllum].

        5 Stems terete; leaves alternate; aerial tubers tan to light brown, usually globose; stem twining from right to left (sinistrorse; looking from below, the stem turns counterclockwise)