Stem-base tuberous, globose. Leaves lanceolate, long-petioled; floating leaves lanceolate-ovate. Spike bifid, dense-flowered; branches 1–1 1/2 in. long; peduncle nearly equal in diameter throughout; flowers rose or purplish. Sepals 1 3/4–2 lin. long, oval-oblong. Stamens 6. Follicles 3, with a beak 2/3 the length of the ovary.
Plants monoecious. Tuber oval, shortly cylindrical or irregularly shaped, 10–30 mm. long and 5–20 mm. thick, densely set with whitish roots above. Leaves few–many; petiole (except in var. graminifolius) 3–60 cm. long and 0.6–3 mm. thick, greenish, terete or somewhat compressed; blade usually oval to lanceolate, floating, with acute to obtuse tip and cuneate to truncate base, very rarely (only in var. cordatus) the base is prominently cordate, 3–12 cm. long and 0.5–5 cm. wide, green, but sometimes dark-spotted beneath; midrib very prominent on lower surface, parallel nerves 2–4 on each side of the midrib; very rarely the leaves sessile, linear and grass-like (in var. graminifolius). Inflorescence a bifid spike 10–50 mm. long and 2–8 mm. wide when flowering, with many usually densely set bisexual or ? flowers facing in all directions; peduncles 5–45 cm. long and 1–5 mm. thick, terete or somewhat flattened, green to reddish; spathe 5–20 mm. long, pale green with darker longitudinal lines (and sometimes spots). Flowers usually consisting of 2 tepals, 6 stamens and 3 ovaries (rarely no stamens and up to 7 ovaries in apomictic plants). Tepals persistent or caducous, pinkish, mauve to bluish violet, rarely white (only in var. albiflorus), oval, obovate to ligulate, or with a narrow base and a wider upper part, 1–5 mm. long, with 1 nerve, rarely densely set with numerous reddish brown gland-dots (only in var. glanduliferus). Stamens 2–3 mm. long; filaments white or violet, somewhat thickened towards the base; anthers 0.2–0.4 mm. long and 0.2–0.3 mm. wide, violet to almost black, but pollen yellow. Follicles grey to brownish, 3–7 mm. long with a prominent 1–2 mm. long beak of the same colour as the remainder of the follicle or much darker, containing 4–14 ovules. Seeds elliptic to elongate, 0.7–1.5 mm. long and 0.2–0.4 mm. wide, with longitudinal ridges, but not prominently winged; testa double.
Tent. Fl. Abyss. 2: 351 (1851); A. Bennett in F.T.A. 8: 218 (1901); E.P.A.: 1202 (1968); H. Bruggen in B.J.B.B. 43: 221, fig. 7/12 (1973) & F.A.C.: 9, photo. facing p. 1 (1974); Lye in U.K.W.F.: 650, fig. p. 651 (1974); H. Bruggen in Bibl. Bot. 33,137: 60 (1985); Lye in Lidia 1: 67 (1986).
in Schimp. Pl. Abyss. Exsicc. 1483. —A. Rich. Tent. Fl. Abyss. ii. 351; Durand & Schinz, Conspect. Fl. Afr. v. 491; Engl. Jahrb. viii. 270.