Lemna aequinoctialis Welw.

Fronds 1-6.5 mm long, 0.8-4.5 mm wide, 1-3 times as long as wide; usually with one papule which is located on the upper surface above the node and is smaller than the one near the tip; wing of the root sheath 1-2 1/2 times as long as wide. INFLORESCENCE: Plants often flowering and fruiting. INFRUCTESCENCE: Fruit 0.5-0.8 mm long, 0.4-0.7 mm wide, not winged; style 0.05-0.20 mm long; seed 0.45-0.80 mm long, 0.3-0.7 mm thick, brownish, with 8-26 distinct longitudinal and 30-80 lateral ribs, falls out of the fruit wall after ripening; outer seed coat with 2-4 subepidermal cell layers.