Oxygonum robustum Germish.

Flora Zambesiaca. Vol. 9, Part 3. Polygonaceae-Myriaceae. Pope GV, Polhill RM, Martins ES. 2006.

Habit

Spreading robust perennial herb, arising from a thick vertical woody rootstock Spreading robust perennial herb, arising from a thick vertical woody rootstock.

Stem

Stems ± decumbent up to 50 cm tall, much branched from the base Stems ± decumbent up to 50 cm tall, much branched from the base.

Leaves

Leaves subsessile; lamina obovate to elliptic or spathulate 3.7–8 × 0.8–2.3 cm, acuminate and apiculate at the apex, attenuate and narrowing gradually into a petiole, entire or more rarely sharply toothed on the margins, glabrous, brown punctate; midrib prominent beneath, sometimes pubescent Leaves subsessile; lamina obovate to elliptic or spathulate 3.7–8 × 0.8–2.3 cm, acuminate and apiculate at the apex, attenuate and narrowing gradually into a petiole, entire or more rarely sharply toothed on the margins, glabrous, brown punctate; midrib prominent beneath, sometimes pubescent.

Ocrea

Ocrea 8–10 mm long, truncate and fringed with ± rigid bristles up to 10 mm long, puberulous to pilose outside, reddish-brown and brown punctate Ocrea 8–10 mm long, truncate and fringed with ± rigid bristles up to 10 mm long, puberulous to pilose outside, reddish-brown and brown punctate.

Flowers

Hermaphrodite flowers homostylous to slightly heterostylous; perianth white, tubular; tube 5 mm long; lobes up to 6 mm long Male flowers not seen Flowers 2–4, pedicellate in the axil of bracts, arranged in terminal and lateral spiciform racemes up to 30 cm long; pedicels up to 5 mm long, glabrous, articulate near the apex; bracts chartaceous, 4–8 mm long, obliquely truncate and produced dorsally into an acute subulate seta, brown punctate outside Flowers 2–4, pedicellate in the axil of bracts, arranged in terminal and lateral spiciform racemes up to 30 cm long; pedicels up to 5 mm long, glabrous, articulate near the apex; bracts chartaceous, 4–8 mm long, obliquely truncate and produced dorsally into an acute subulate seta, brown punctate outside. Male flowers not seen. Hermaphrodite flowers homostylous to slightly heterostylous; perianth white, tubular; tube 5 mm long; lobes up to 6 mm long.

Filaments

Filaments 4–5 mm long; anthers up to 1 mm long, oblong, reddish-brown

Ovary

Ovary up to 3 mm long, 3 angled; styles 3 mm, connate at the base

Fruits

Nut immature, 3 angled, up to 6 mm long, longitudinally ridged, ± narrowly winged, pubescent. Nut immature, 3 angled, up to 6 mm long, longitudinally ridged, ± narrowly winged, pubescent.

Ecology

Coastal grasslands.

Distribution

Also in South Africa (KwaZulu-Natal). Mozambique MOZ M

Male

Male flowers not seen.

Hermaphrodite

Hermaphrodite flowers homostylous to slightly heterostylous; perianth white, tubular; tube 5 mm long; lobes up to 6 mm long. Ovary up to 3 mm long, 3 angled; styles 3 mm, connate at the base. Filaments 4–5 mm long; anthers up to 1 mm long, oblong, reddish-brown.

Stamens

Filaments 4–5 mm long; anthers up to 1 mm long, oblong, reddish-brown.

Pistil

Ovary up to 3 mm long, 3 angled; styles 3 mm, connate at the base.