Sagittaria sagittifolia, L.

1. S. sagittifolia L. View in CoL , Sp. Pl. 993 (1753).

Monoecious. Aerial leaves broadly to narrowly sagittate with 2 long acute basal lobes; floating leaves (if present) lanceolate to ovate. Flowers in racemes or panicles; at least the lower bracts free. Petals 10-15 mm, white, usually with a purple patch at the base. Filaments of stamens linear, glabrous; anthers usually purple, Fruitlets 4-6 mm, with a short, erect, apical beak. 2n = 22. Most ofEurope, but rare in the extreme north and extreme south. Au Be Br Bu Cz Da Fe Ga Ge Gr Hb He Ho Hs Hu It Ju Lu No Po Rm Rs (N, B, C, W, E) Sa Su Tu.

S. trifolia L. , Sp. PI. 993 (1753), widespread in Asia, has recently been reported from S.E. Russia (where it is believed to be native in the Volga delta) and S. Ukraine (where it is naturalized). It is like 1 but with the basal lobes of the aerial leaves longer in proportion to the rest of the lamina, and with entirely white petals and yellow anthers.