Ottelia exserta (Ridl.) Dandy

exserta: projecting, protruding

Aquatic herb, 20-50 cm high. Leaves submerged when young, floating or even erect above the surface of the water, more or less broadly ovate, 3.5-13.5 cm long, 1.5-2.5 times longer than wide, leathery with 5-7 prominent longitudinal veins; margin entire and smooth; petiole distinct, 9-45 cm long, triangular in cross-section. Inflorescences unisexual on different plants, rarely on the same plant. Male inflorescences with peduncle 6-47 cm long, spathes ovoid, oblong or lanceolate, 3.5-7.5 cm long, flattened, often 2-winged. Flowers 6-40 per spathe, 1-4 opening at the same time, pedicels exserted c. 4 cm above the spathe; sepals lanceolate, 8-12(-21) mm long, with darker veins and tips; petals obovate, white with cream or yellowish base. Female inflorescences with peduncle 16-20.5 cm long, spathes narrowly ovoid, 3-6 cm long, unwinged, grooved with c. 10 darker longitudinal stripes, smooth or with very small prickles. Flowers 1 per spathe, exserted 6-17 cm above the spathe; sepals oblong-lanceolate, 8-16(-23) mm long; petals obovate, white with yellowish base. Fruit spindle-shaped, 2.5-4 cm long.

Locally common

Angola, Namibia (Caprivi), Somalia, Kenya, Tanzania, Malawi, Mozambique, Zambia, Zimbabwe and South Africa.

Ottelia exserta là một loài thực vật có hoa trong họ Hydrocharitaceae. Loài này được (Ridl.) Dandy mô tả khoa học đầu tiên năm 1934.