Sagittaria teres S.Watson

Herbs, perennial, to 80 cm; rhizomes absent; stolons present; corms present. Leaves emersed or submersed, sessile, phyllodial, nearly terete; emersed, to 60 ´ 0.15--0.7 cm; submersed, 3.5--18.5 ´ 0.15--0.4 cm. Inflorescences racemes, of 1--4 whorls, emersed, 2.5--4 ´ 2.5--6 cm; peduncles 10--80 cm; bracts connate more than or equal to total length, subulate, 2--3 mm, delicate, not papillose; fruiting pedicels obliquely ascending, filiform, 1 cm. Flowers to 1.5 cm diam.; sepals recurved, not enclosing flower; filaments dilated, ± equaling anthers, pubescent; pistillate pedicellate, without ring of sterile stamens. Fruiting heads 0.6--1 cm diam.; achenes obovoid-cuneate, abaxially keeled, 2--3 ´ 1.2--1.5 mm, beaked; faces not tuberculate, wings absent, glands 1--2; beak erect to horizontal, 0.3--0.4 mm. 2n = 22.