Herbs, perennial, to 35 cm; rhizomes absent; stolons present; corms present. Leaves submersed and emersed; submersed phyllodial, flattened, 9.5--16.5 ´ 0.6--1.5 cm; emersed with petiole nearly terete, 3--25 cm, blade linear-lanceolate to ovate, 5.5--8.5 ´ 0.5--2.1 cm. Inflorescences racemes, of 2--5 whorls, emersed, 4.5--15 ´ 2--6 cm; peduncles to 35 cm; bracts connate ¼ total length, lanceolate, 2--4.5 mm, delicate, not papillose; fruiting pedicels spreading to recurved, cylindric, 1.5--4.5 cm. Flowers to 1 cm diam.; sepals appressed to spreading, not enclosing flower or fruiting head; filaments dilated, ± equaling anthers, glabrous; pistillate pedicellate, without ring of sterile stamens. Fruiting heads 0.5--0.6 cm diam; achenes obovoid, abaxially keeled, 2.5--3 ´ 1.2--1.5 mm, beaked; faces not tuberculate, wings 1, ± entire, glands 0--1; beak lateral, horizontal, ca. 0.5 mm. Flowering spring--summer. Swamps, bogs, and wet roadside ditches; of conservation concern; 250--1000 m; N.C., S.C.