1 Well-developed leaves with sagittate base (the lobes pointing downward, essentially parallel to the petiole); inner tepals of carpellate flowers 4-6 mm long (at fruiting), 1 or more with a tubercle; tepals of staminate flowers 2.0-3.0 mm long; achenes 2.0-2.5 mm long; plant perennial from a rhizome

1 Well-developed leaves with hastate base (the lobes divergent, pointing outward, at about 90 degrees from the petiole); inner tepals of carpellate flowers 1.2-3.5 mm long (at fruiting), none with a tubercle; tepals of staminate flowers 1.5-2.0 mm long; achenes 0.9-1.5 mm long; plant either perennial from a rhizome or annual from a taproot.

  2 Inner tepals (at fruiting) 1.2-1.7 (-2.0) mm long, about as long and wide as the achene, with a minute or absent free wing; pedicel jointed just below the tepals; plant perennial, from a thin, creeping rhizome

  2 Inner tepals (at fruiting) 2.5-3.2 mm long, much longer and wider than the achene, with an expanded, accrescent wing that develops prominent reticulate veins; pedicel jointed near its middle or base, well below the tepals; plants annual or short-lived perennials; from a taproot