미국, 캐나다, 멕시코, 유럽, 인도, 중국, 일본, 몽골, 러시아, 한국 (경북 안동, 경기 부천)
개요
Annual or perennial floating herbs, Fronds ovate to elliptic, 1–4(–6) cohere in one plant, veins 1–3, 4–7(–9) similar sized papillae on midvein, 2.7–3.1 mm long, 1.9–2.2 mm wide, 1.4–1.8 times as long as wide, 0.6–0.8 mm thick, upper frond usually green, sometimes reddish purple to purplish with pigment, lower frond usually pigmented; Bisexual flower in the budding pouch in frond, protogynous, ovary 0.3–0.4 mm long, 0.2–0.3 mm diameter, style 0.2–0.3 mm long, stamen 0.4 mm long, spathe reddish colored, 0.9–1.1 mm long, 0.8–1.0 mm diameter; anther 0.2 mm long, 0.2 mm diameter. Turion very widely ovate to very widely obovate, tinged dark purple to brown, 0.97–1.29 mm long, 0.86–1.18 mm wide; root solitary, root tip obtuse, root cap 0.8–2.1 mm long, 0.2–0.3 mm diameter, root 0.8–2.3 cm long, root base dark purple–colored. No fruits and seeds had been seen in Korea.
