Pterocarpus rotundifolius (Sond.) Druce

Flora Zambesiaca Leguminosae subfamily Papillionoideae byJ.M. Lock*

Morphology General Indumentum

Young parts greyish-sericeous or fulvous-pubescent; branchlets pubescent-glabrescent or glabrous; bark grey or reddish, smooth. Young parts greyish-sericeous or fulvous-pubescent; branchlets pubescent-glabrescent or glabrous; bark grey or reddish, smooth.

Morphology Leaves

Leaves 12–35 cm long; petiole 3–7 cm long, rachis 6–15 cm long, pubescent or glabrous; petiolules 2–20 mm long, puberulous or glabrous; leaflets 3–19(21), alternate, opposite or subopposite, 2–10 × 2–7 cm, circular to elliptic or ovate, occasionally obovate or oblong-subelliptic, rounded or broadly retuse or shortly and bluntly acuminate to acuminate-acute at the apex, rounded or obtuse at the base, coriaceous or thin and stiff, glabrous on upper surface, paler and appressed-pubescent beneath; lateral nerves in 6–14 pairs; stipules 4–8 mm long, caducous. Leaves 12–35 cm long; petiole 3–7 cm long, rachis 6–15 cm long, pubescent or glabrous; petiolules 2–20 mm long, puberulous or glabrous; leaflets 3–19(21), alternate, opposite or subopposite, 2–10 × 2–7 cm, circular to elliptic or ovate, occasionally obovate or oblong-subelliptic, rounded or broadly retuse or shortly and bluntly acuminate to acuminate-acute at the apex, rounded or obtuse at the base, coriaceous or thin and stiff, glabrous on upper surface, paler and appressed-pubescent beneath; lateral nerves in 6–14 pairs; stipules 4–8 mm long, caducous.

Morphology Reproductive morphology Inflorescences

Inflorescence a terminal (rarely also axillary) panicle up to 30 cm long, appressed-pubescent or glabrous; bracts and bracteoles caducous. Inflorescence a terminal (rarely also axillary) panicle up to 30 cm long, appressed-pubescent or glabrous; bracts and bracteoles caducous.

Morphology Reproductive morphology Flowers

Flowers 14–17 mm long; pedicels 2–14(18) mm long, puberulous or glabrous. Flowers 14–17 mm long; pedicels 2–14(18) mm long, puberulous or glabrous.

Morphology Reproductive morphology Flowers Calyx

Calyx 5–7 mm long, pubescent inside the teeth, otherwise glabrous or puberulous; upper teeth shallow, rounded, the lateral ones obtuse, the lower one c.2.5 mm long, acute. Calyx 5–7 mm long, pubescent inside the teeth, otherwise glabrous or puberulous; upper teeth shallow, rounded, the lateral ones obtuse, the lower one c.2.5 mm long, acute.

Morphology Reproductive morphology Flowers Corolla

Standard 13–15 mm in diameter, circular, claw c.4 mm long; wings as long as the standard, auricle obtuse, claw 4–5 mm long; keel petals shorter than the wings, arcuate, claw 4.5 mm long. Standard 13–15 mm in diameter, circular, claw c.4 mm long; wings as long as the standard, auricle obtuse, claw 4–5 mm long; keel petals shorter than the wings, arcuate, claw 4.5 mm long.

Morphology Reproductive morphology Flowers Androecium Stamens

Stamens 10, all fused. Stamens 10, all fused.

Morphology Reproductive morphology Flowers Gynoecium Ovary

Ovary 3–4-ovulate, glabrous, or sparsely pilose on the margins, or densely pubescent; stipe c.4 mm long, appressed-pubescent. Ovary 3–4-ovulate, glabrous, or sparsely pilose on the margins, or densely pubescent; stipe c.4 mm long, appressed-pubescent.

Morphology Reproductive morphology Fruits

Pod 1–2-seeded, 3–6 cm long, obovate to broadly elliptic or oblong, somewhat incurved, rounded and raised-nerved in centre; style remains at the apex or nearly so. Pod 1–2-seeded, 3–6 cm long, obovate to broadly elliptic or oblong, somewhat incurved, rounded and raised-nerved in centre; style remains at the apex or nearly so.

Morphology Reproductive morphology Seeds

Seeds 6–7 × 3–4 × 2.5 mm; testa dark brown, smooth. Seeds 6–7 × 3–4 × 2.5 mm; testa dark brown, smooth.

Morphology General Habit

Deciduous tree up to 18 m tall; crown rounded; bark grey or brown, flaking off in scales. Deciduous tree up to 18 m tall; crown rounded; bark grey or brown, flaking off in scales.

Leguminosae, J. B. Gillett, R. M. Polhill & B. Verdcourt. Flora of Tropical East Africa. 1971

Morphology General Habit

Tree, 3–20 m. tall, or at limits of range in southern Africa a several-stemmed shrub, with irregular rounded crown, ± deciduous; bark scaling or reticulately fissured, light grey or brown; slash exuding red gum.

Morphology Branches

Branchlets pubescent to tomentellous, glabrescent.

Morphology Leaves

Leaves (11–)17–40 cm. long; stipules linear, up to 1–1.5 cm. long, fugaceous; lateral leaflets 1–9 on either side, subopposite to markedly alternate, ovate or oblong-ovate to variously elliptic or suborbicular, up to 6–11 cm. long and 3–7 cm. wide, shortly and bluntly acuminate to rounded and emarginate at apex, cuneate to rounded at base, with short fine appressed or spreading indumentum variously developed beneath, rarely glabrous; primary lateral nerves curved-ascending, 10–14on either side; venation prominulous or fine and flat.

Morphology Reproductive morphology Flowers

Flowers produced in profusion in mostly terminal laxly branched spreading panicles up to 12–40 cm. long; bracts linear-lanceolate, 1–2 mm. long, fugaceous; bracteoles at top of 3–10 mm. long pedicels similar.

Morphology Reproductive morphology Flowers Calyx

Calyx 6–7 mm. long, glabrous outside in East Africa (sometimes pubescent further south), with pubescence on the lobes inside; lobes up to half as long as the tube.

Morphology Reproductive morphology Flowers Corolla

Corolla 12–18 mm. long, yellow or orange-yellow, fragrant; standard with a broadly obovate or suborbicular blade, reflexed, marginally crimped; wings broadly expanded, enveloping the keel.

Morphology Reproductive morphology Fruits

Fruit shortly stipitate, elliptic-oblong, rounded rather more on the lower side, or ± semi-orbicular, the wing relatively narrow, coriaceous, and scarcely produced to the subterminal style-base, 4–6.5 cm. long, 2.5–3.5(–4) cm. wide, glabrous or (outside East Africa) pubescent, radially venose.

Distribution

T6 T8 south to the Transvaal and westwards to the Congo and Angola

IUCN Red List of Threatened Species https://www.iucnredlist.org/species/146213831/146213833

Conservation

LC - least concern

Extinction risk predictions for the world's flowering plants to support their conservation (2024). Bachman, S.P., Brown, M.J.M., Leão, T.C.C., Lughadha, E.N., Walker, B.E. https://nph.onlinelibrary.wiley.com/doi/full/10.1111/nph.19592

Conservation

Predicted extinction risk: not threatened. Confidence: confident