Pterocarpus megalocarpus Harms

Flora Zambesiaca Leguminosae subfamily Papillionoideae byJ.M. Lock*

Morphology General Habit

Evergreen tree up to 20 m tall. Evergreen tree up to 20 m tall.

Morphology Stem

Stem with buttresses at the base (Pedro & Pedrógão 5272); bark dark, flaking off in plates; crown spreading or round. Stem with buttresses at the base (Pedro & Pedrógão 5272); bark dark, flaking off in plates; crown spreading or round.

Morphology Branches

Branchlets terete, bark brown, appressed-pubescent, interspersed with ± dense hispid reddish glandular hairs, 1–2 mm long. Branchlets terete, bark brown, appressed-pubescent, interspersed with ± dense hispid reddish glandular hairs, 1–2 mm long.

Morphology Leaves

Leaves 18–22 cm long; petiole 2–3 cm long, rachis 9–11 cm long, hispid-glandular; petiolules 5–6 mm long, appressed-pubescent; leaflets 3–4 on each side of the rachis, alternate, 2–9 × 2.5–4 cm, ovate or elliptic to obovate, usually abruptly and shortly acuminate, often slightly emarginate at the apex, thin and stiff, deep green and glabrous on upper surface (when mature), paler and sparsely strigulose beneath; lateral nerves in 7–12 pairs, reticulation rather close, conspicuous on both surfaces; stipules caducous. Leaves 18–22 cm long; petiole 2–3 cm long, rachis 9–11 cm long, hispid-glandular; petiolules 5–6 mm long, appressed-pubescent; leaflets 3–4 on each side of the rachis, alternate, 2–9 × 2.5–4 cm, ovate or elliptic to obovate, usually abruptly and shortly acuminate, often slightly emarginate at the apex, thin and stiff, deep green and glabrous on upper surface (when mature), paler and sparsely strigulose beneath; lateral nerves in 7–12 pairs, reticulation rather close, conspicuous on both surfaces; stipules caducous.

Morphology Reproductive morphology Inflorescences

Inflorescence (in East African material) of panicles in axils of upper leaves, 10–19 cm long, with a few lax rather spreading primary branches, many-flowered; bracts 1–3 mm long, lanceolate to ovate, caducous; bracteoles 3–6 mm long; pedicel small and narrow. Inflorescence (in East African material) of panicles in axils of upper leaves, 10–19 cm long, with a few lax rather spreading primary branches, many-flowered; bracts 1–3 mm long, lanceolate to ovate, caducous; bracteoles 3–6 mm long; pedicel small and narrow.

Morphology Reproductive morphology Fruits

Pod 1-seeded, stipitate, circular, 14.5 cm in diameter (Mozambique material); wing papyraceous, undulate and flaccid, sparsely pubescent, sometimes with a few scattered bristly hairs, asymmetric at the base, style-insertion bent down overlapping the stipe and producing a deep narrow sinus, thickened-umbonate over the seed, quite glabrous (when ripe). Pod 1-seeded, stipitate, circular, 14.5 cm in diameter (Mozambique material); wing papyraceous, undulate and flaccid, sparsely pubescent, sometimes with a few scattered bristly hairs, asymmetric at the base, style-insertion bent down overlapping the stipe and producing a deep narrow sinus, thickened-umbonate over the seed, quite glabrous (when ripe).

Distribution

Also in SE Tanzania.

Ecology

Coastal and riverine forest; 0–600 m.

Conservation

Conservation notes: Within the Flora Zambesiaca area known from only a single collection, and from only a few collections overall. Probably best assessed as Vulnerable B1.

Morphology Reproductive morphology Flowers Calyx

Calyx 5.5–7 mm long, ± densely covered with short appressed brownish hairs outside and on the lobes inside. Calyx 5.5–7 mm long, ± densely covered with short appressed brownish hairs outside and on the lobes inside.

Morphology Reproductive morphology Flowers Corolla

Corolla 11–13 mm long, cream or yellow, fragrant; standard broadly ovate; wings broadly expanded, enveloping the keel and nearly as long as the standard. Corolla 11–13 mm long, cream or yellow, fragrant; standard broadly ovate; wings broadly expanded, enveloping the keel and nearly as long as the standard.