Apparently glabrous aquatic with all submerged parts covered with a profuse clear slimy jelly-like mucilage; the outsides of the sepals and petals, the undersurfaces of the leaves, submerged petioles, pedicels, etc., are covered with minute purplish glandular hairs which may secrete this mucilage. Leaf-blades round or broadly elliptic, 2.5–11.5 cm. long, 1.5–7 cm. wide, entire, green above, usually reddish-brown or purplish beneath with 12 nerves radiating from the centre; petiole-length depending on the depth of the water, 0.05–1 m. long or more, slender, ±1.5 mm. in diameter. Pedicels reddish-brown, 4–5 cm. long, 2 mm. in diameter. Sepals purplish- or brownish- red, elliptic or narrowly oblong, 0.9–1.4 cm. long, 3–6 mm. wide, rounded atthe apex. Petals crimson, purplish- or brownish-red, narrowly oblong or linear-oblong, 1.2–1.7 cm. long, 3–4 mm. wide, narrowly rounded at the apex. Filaments of the stamens filiform, 1 cm. long, papillose; anthers reddish, linear-oblong, 3.5 mm. long, apiculate. Carpels fusiform or narrowly ovoid, 5 mm. long, 1.5–2 mm. wide, sparsely papillose; stigma simple, 3–4.5 mm. long, papillose all over save for a narrow longitudinal area facing the perianth. Fruiting carpels ellipsoid or fusiform, 0.6–1 cm. long, 2–2.5 mm. wide; stigma persistent. Seeds pale brown, ellipsoid, 2.7–3.5 mm. long, 2–2.3 mm. wide.
Glabrous aquatic plant with all its submerged parts covered with a profuse, clear, slimy mucilage. Leaves floating, rotund, peltate, 7.5 (10) x 5–7 cm., margin entire, green above, reddish-brown or purplish below, nerves 12, radiating from the apex of the petiole, rather faint, petiole reddish-brown, attached at the centre of the leaf-blade, up to 1 m. or more long according to the depth of the water, c. 1.5 mm. in diam. Flowers solitary, axillary on reddish-brown peduncles up to c. 8 cm. long, c. 2 mm. in diam. Sepals purplish-brownish-red, petaloid, c. 1.4 x 0.3 cm., narrowly oblong, apex rounded. Petals similar to the sepals but slightly larger. Stamens with slender papillose filaments up to 1 cm. long; anthers reddish, 3.5 mm. long, narrowly oblong, apiculate at the apex. Carpels 5 x 2 mm., narrowly lanceolate-ovoid, sparsely papillose, stigma simple, 3 mm. long, papillose. Ripe carpels 7 x 2 mm., ellipsoid with a persistent stigma. Seeds 3.5 x 2.3 mm., ellipsoid, testa pale brown.
Zambia Lake Bangweulu, Kamindas, fl. 13.x.1911, Fries 1001 (UPS).
Botswana Okovango Swamps, near 22° 30´ E, 19° 5´ S., fl. 28.ix.1954, Story 4786 (K; PRE).
Kenya Equator, Lake Narasha, 16 Oct. 1953, Drummond & Hemsley 4802 !
Zambia Ngambi (Ngambwe) Swamps, fr., Gilges 7 (PRE).
Tanzania Kongolero Lake, Sept. 1931, Haarer 2184!;
Tanzania Ukinga, Bulongwa, 26 Jan. 1914, Stolz 2463 !
Uganda E. side of Lake Nabugabo, 6 Oct. 1953, Drummond & Hemsley 4628!;
Uganda Kyagwe [Kiagwe], Namanve Swamp, Sept. 1932, Eggeling 563 ! & Kampala, King's Lake, 21 July 1935, Chandler & Hancock 12 !
in L., Syst. Nat. ed. 13, 2: 853 (1791). — Exell & Mendonça, C.F.A. 1 1: 45 (1937). TAB. 25 Type from United States of America (N. Jersey).
in L., Syst. Nat., ed. 13, 2: 853 (1791); Chifflot in Annls. Univ. Lyon, Fasc. 10: 39–49 (1902); Exell & Mendonça in C.F.A. 1: 45 (1937); Flora U.R.S.S. 7: 5, t. 1/3 (1937); Gleason, New Britton & Brown Illustr. Fl. 2: 148, fig. (1952); Wild in F.Z. 1: 173, t. 25 (1960); F.P.U.: 46 (1962); Meusel & Mühlberg in Hegi, Illustr. Fl. Mitteleuropa 3 (3), 1: 7, fig. 4 (1965) [map of recent and fossil distribution].