Volume 4 > Part 3.3 > Year 2023 > Page 707 > Leguminosae-Papilionoideae > Vigna

15. Vigna trinervia (B.Heyne ex Wight & Arn.) Tateishi & Maxtedwfo-0000418132

Kew Bull. 57(3): 633. 2002; N.Tomooka et al., Asian Vigna: 101, f. 4.34, 4.35. 2002.— Phaseolus trinervius B.Heyne [in Wall., Numer. List: 5603. 1831–1832, nom. nud.] ex Wight & Arn., Prodr. Fl. Ind. Orient. 1: 245. 1834.

Accepted Name : Vigna radiata var. radiata

Description : Perennial herb; stems twining, sparsely to densely retrorse brown villous. Stipules peltate, oblong or elliptic, 10–11 by 3.5–4.5 mm, apex acute, base obtuse or rounded, margin entire, sparsely villous along margin, persistent. Leaves: petioles 4–9 cm long, sparsely to densely retrorse brown villous; rachis 1–1.3 cm long, sparsely retrorse brown villous. Leaflets sometimes shallowly 3-lobed, both surfaces sparsely white hispid; lateral veins 6–8 pairs; terminal leaflet ovate or ovate-lanceolate, 8–9 by 4–5 cm, apex acute or acuminate, base obtuse or round, margin entire; lateral leaflets obliquely ovate, 7–8 by 4.5–5 cm, apex acute or acuminate, base truncate, margin entire; petiolules ca 3 mm long, densely villous; stipels linear, 4–5 by ca 0.8 mm, apex attenuate or acuminate, glabrous. Inflorescence axillary, 4–8-fascicled, arranged in nodose-pseudoracemes; peduncles 22–24 cm long, sparsely brown pubescent; axis 0.8–1.5 cm long, sparsely brown pubescent; bracts broadly ovate or suborbicular, ca 3 by 2.5 mm, apex acute, sparsely pubescent. Flowers 1–2 in each fascicle, bright yellow; pedicels ca 1.5 mm long, sparsely to densely pubescent; bracteole attached to the pedicel elliptic, 4.5–5 by 2–2.5 mm, apex acute, sparsely pubescent, caducous; bracteoles ppressed to the base of calyx tube elliptic, 5.5–7 by 1.5–1.8 mm, longer than calyx, apex attenuate, outside and along margin sparsely pubescent, inside glabrous, persistent. Calyx: tube 2.5–3 by 3.5–4 mm; upper lobes connate, apex divided to form shallow lobes; lower lobes deltoid, ca 1 by 1 mm, apex acute, sparsely pubescent along margin. Corolla: standard obliquely reniform, 1–1.1 by 1.6–1.7 cm, inside with 1 appendage at centre, apex emarginate; wings obovate, 0.9–1.1 by 0.7–0.8 cm, apex obtuse, near the base with 1 appendage, 1–1.2 mm long, claw 1.5–2.5 mm long; keel falcate, 1.5–1.7 by 0.5–0.6 cm, spirally incurved upward to beak, the left petal with a horn-like pocket, 4–4.5 mm long. Stamens: filaments 1.9–2 cm long; anthers elliptic, ca 0.5 mm long. Pistil 2–2.2 cm long; ovary linear, pubescent; beak beyond the stigma ca 0.8 mm long. Pods: linear, 5–7 by 0.3–0.4 cm, spreading, sparsely to densely brown hispid, base shortly stipitate; fruit stalk 3–5.5 mm long, sparsely pubescent. Seeds 11–14, dry seeds dark brown with black dots, rectangular, ca 3 by 2.5 mm, without aril.

Thailand : NORTHERN: Chiang Mai (Mae Kuang), Chiang Rai (Mae Sai).

Distribution : Tanzania, Comoros Islands, Madagascar, India (type), Sri Lanka, Myanmar, Indonesia, the Philippines.

Ecology : Roadsides, paddy fields or near flooded areas; 350–550 m alt. Flowering and fruiting: October–December.