Sesbania tetraptera Hochst. ex Baker

Flora Zambesiaca Leguminosae subfamily Papillionoideae by G.P. Lewis

Morphology General Habit

Erect annual or biennial herb 1–4 m tall, sometimes with wide regular branching. Erect annual or biennial herb 1–4 m tall, sometimes with wide regular branching.

Morphology Stem

Stems greenish or tinged purplish-blue, sparsely pilose when young, glabrous later, sometimes with a few to many scattered prickles. Stems greenish or tinged purplish-blue, sparsely pilose when young, glabrous later, sometimes with a few to many scattered prickles.

Morphology Leaves

Leaves (5.5)7–38 cm long, the rachis sparsely pilose on the upper surface, sometimes sparsely aculeate below; petioles (0.2)0.3–1.8(3.5) cm long; leaflets in (9)16–42 pairs, 0.8–4.3 cm × 2–10.5 mm, often purplish beneath, oblong, apiculate, occasionally obscurely pilose on margins and midvein beneath, otherwise glabrous; stipules 5–10 mm long, narrowly lanceolate, pilose, usually spreading and persistent, often with a curled apex. Leaves (5.5)7–38 cm long, the rachis sparsely pilose on the upper surface, sometimes sparsely aculeate below; petioles (0.2)0.3–1.8(3.5) cm long; leaflets in (9)16–42 pairs, 0.8–4.3 cm × 2–10.5 mm, often purplish beneath, oblong, apiculate, occasionally obscurely pilose on margins and midvein beneath, otherwise glabrous; stipules 5–10 mm long, narrowly lanceolate, pilose, usually spreading and persistent, often with a curled apex.

Morphology Reproductive morphology Inflorescences

Raceme 3.4–16.2 cm long, 2–13-flowered; peduncle 1.8–7 cm long, beset, often densely so, with flattened, sometimes fused prickles especially at the base, the prickles occasionally tipped with hairs; pedicels 0.4–2.1 cm long, glabrous; bracts 3–5.5 mm long, linear to narrowly lanceolate, spreading, caducous or persisting until after the corolla has fallen off; bracteoles 2–4 mm long, linear-lanceolate, caducous. Raceme 3.4–16.2 cm long, 2–13-flowered; peduncle 1.8–7 cm long, beset, often densely so, with flattened, sometimes fused prickles especially at the base, the prickles occasionally tipped with hairs; pedicels 0.4–2.1 cm long, glabrous; bracts 3–5.5 mm long, linear to narrowly lanceolate, spreading, caducous or persisting until after the corolla has fallen off; bracteoles 2–4 mm long, linear-lanceolate, caducous.

Morphology Reproductive morphology Flowers Calyx

Calyx 4–7 × 4.5–8 mm; tube glabrous; teeth 0.5–1.5 mm long, acuminate, marginally hairy. Calyx 4–7 × 4.5–8 mm; tube glabrous; teeth 0.5–1.5 mm long, acuminate, marginally hairy.

Morphology Reproductive morphology Flowers Corolla

Standard pale yellow with dark purple speckling on the outer face, 0.9–2 × 0.8–1.8 cm, broad, rounded, apically emarginate, the blade often wider than long, sometimes prominently cordate basally, the appendages gently rounded and without free tips; wings yellow, 1–2 cm × 3–6 mm, with an upper basal very slightly downward-pointing tooth and with lamellate sculpturing in the upper basal section on outer face; keel pale yellow to greenish-yellow, 0.7–1.6 cm × 5–9 mm; basal tooth usually at an angle of 10–30° with the claw but occasionally at 45° (e.g. Richards 14469). Standard pale yellow with dark purple speckling on the outer face, 0.9–2 × 0.8–1.8 cm, broad, rounded, apically emarginate, the blade often wider than long, sometimes prominently cordate basally, the appendages gently rounded and without free tips; wings yellow, 1–2 cm × 3–6 mm, with an upper basal very slightly downward-pointing tooth and with lamellate sculpturing in the upper basal section on outer face; keel pale yellow to greenish-yellow, 0.7–1.6 cm × 5–9 mm; basal tooth usually at an angle of 10–30° with the claw but occasionally at 45° (e.g. Richards 14469).

Morphology Reproductive morphology Flowers Gynoecium Ovary

Ovary winged, 15–32-ovulate, glabrous; style pubescent except at the base.

Morphology Reproductive morphology Fruits

Pod (8.3)12–23.3 × (0.9)1–1.4 cm, linear or slightly curved, shortly beaked, stipitate, 4-winged, (9)19–28-seeded, glabrous; wings darker than the central window-like areas above the seeds except in very old fruit; septa 6–8 mm apart. Pod (8.3)12–23.3 × (0.9)1–1.4 cm, linear or slightly curved, shortly beaked, stipitate, 4-winged, (9)19–28-seeded, glabrous; wings darker than the central window-like areas above the seeds except in very old fruit; septa 6–8 mm apart.

Morphology Reproductive morphology Flowers Gynoecium Pistil

Ovary winged, 15–32-ovulate, glabrous; style pubescent except at the base.

Morphology Reproductive morphology Seeds

Seeds ochre, olive-green sometimes over-coloured bluish-black, brown or reddish-brown, 4–5.5 × 2–4 mm, 1.5–2.5 mm thick, ellipsoid to brick-shaped; hilum in small subcentral circular pit surrounded by a rim aril. Seeds ochre, olive-green sometimes over-coloured bluish-black, brown or reddish-brown, 4–5.5 × 2–4 mm, 1.5–2.5 mm thick, ellipsoid to brick-shaped; hilum in small subcentral circular pit surrounded by a rim aril.