Vigna pygmaea R.E.Fr.

Leguminosae, B. Mackinder, R. Pasquet, R. Polhill and B. Verdcourt. Flora Zambesiaca 3:5. 2001

Habit

Short erect pyrophytic herb with several stems 3–15 cm tall, flowering when quite leafless, arising from slender underground rhizomes 1–1.5 mm thick (but sometimes swollen into a small knot at ground level) which in turn bear beneath them slender fusiform tubers up to 6 × 1 cm.

Stem

Stem weakly pubescent.

Leaflets

Leaflets 3, 1–8 × 0.5–3 cm, elliptic- to linear-oblong, acute at the apex, rounded or subcordate at the base, almost glabrous or with short appressed bristly pubescence on both surfaces; tertiary venation parallel; petiole 1.5–8 cm long; rhachis 1–6 mm long; stipules 2–11 × 1–1.8 mm, lanceolate, almost truncate or slightly bilobed at the base, 3-nerved to multinerved, much more reduced in size on leafless stems than on leafy stems.

Inflorescences

Inflorescence axillary although appearing terminal; peduncle 0–17 cm × 0.3–0.8 mm; rhachis 1–3-noded, internodes 1–20 mm long.

Flowers

Flower pale to deep mauve or violet, 9–12 mm long; pedicel 1–3 mm long, not expanding as the pod matures; bracteoles 1.2–1.5 × 0.5 mm, lanceolate, 3–5-nerved.

Calyx

Calyx glabrescent to densely covered with white and blackish-brown appressed or spreading bristly pubescence; tube 2–3 mm long; lobes subequal, 1–4 mm long, the upper pair joined for a half to a third of their length.

Corolla

Standard with 2 parallel widely spaced appendages and two smaller internal appendages; keel without a beak, slightly twisted towards the left.

Ovary

Ovary 8–11-ovuled.

Fruits

Pods 3–4 cm × 2.5–3 mm, linear-cylindrical, densely covered with short appressed or spreading bristly white and dark brown pubescence, with a curved beak.

Seeds

Seed 2–2.5 × 2–2.5 mm; hilum central, 0.5 mm long; rim aril not developed.