Macroptilium atropurpureum

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Flowers and pods, and trifoliolate leaf.

Flowers, dehiscent pods, and seeds.


Vigorous twining stems.

Cv. Siratro climbing Panicum maximum cv. Hamil stems.

cv. Aztec in light shade in Chautara, Nepal.

Rust symptoms on cv. Siratro leaves.

A mixed cv. Siratro and Paspalum plicatulum pasture in northern Australia.

Suction harvesting of cv. Siratro seed in northern Australia.

From:‘t Mannetje, L. and Jones, R.M. (1992) Plant Resources of South-East Asia No. 4. Forages. (Pudoc Scientific Publishers, Wageningen, the Netherlands). © Prosea Foundation.

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Scientific name

Macroptilium atropurpureum (DC.) Urb.


Macroptilium atropurpureum (DC.) Urb. var. atropurpureum
Macroptilium atropurpureum (DC.) Urb. var. canescens (M.Martens & Galeotti) Hassl.
Phaseolus affinis Piper
Phaseolus atropurpureus DC. [basionym]
Phaseolus canescens M.Martens & Galeotti
Phaseolus dysophyllus Benth.
Phaseolus schiedeanus Schldl.
Phaseolus vestitus Hook.


Family: Fabaceae (alt. Leguminosae) subfamily: Faboideae tribe: Phaseoleae subtribe: Phaseolinae. Also placed in: Papilionaceae.

Common names

atro, siratro, purple-bean, purple bush-bean (English);  purpurbohne (German);  conchito (Spanish).

Morphological description

Perennial herb with deep, swollen taproot and trailing, climbing and twining stems.  Stems at the base of older plants fibrous, >5 mm diameter;  younger stems mostly 1-2 mm diameter, pubescent to densely pilose with white hairs;  occasionally forming nodal roots under ideal conditions.  Leaves trifoliolate;  leaflet blades 2-7 x 1.5-5 cm, darker green and finely hairy on the upper surface, grey-green, pubescent on the lower surface, with leaf margins sparsely to densely, finely ciliate.  Lateral leaflets ovate to narrowly elliptical, obtuse, mostly with one or two, shallow to deep lobes on the outer margin;  terminal leaflet rhomboid, with or without single lobe either side.  Inflorescence a raceme comprising 6-12 often paired flowers on a short rachis, pe