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..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
......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]
........5 Stems with 2-4 wings or angles (these often purplish); leaves alternate below, opposite and decussate above; aerial tubers dark-brown and elongate; stem twining from left to right (dextrorse; looking from below, the stem turns clockwise)
........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)