Dioscorea sansibarensis Pax

Etymology Genus After Pedanios Dioscorides, a Greek pharmacologist
Species From Zanzibar islands
Family Dioscoreaceae
Synonyms Dioscorea macroura Harms, Dioscorea maciba Jum. & H.Perrier
Common Names Zanzibar Yam
Status Exotic: Naturalised
Form Climber
Native Distribution Tropical Africa


A sun-loving climber commonly found along forest edges. The leaves have a unique bat-like shape, and comes with depressed venation and extended drip trips. Brown bulbils sometimes formed as a pair at the leaf axils, resembling a pair of testicles.

Interesting Facts:

This poisonous African yam was first introduced for experimental purposes in the Singapore Botanic Gardens (Holttum, 1964), but has escaped cultivation since. It doesn't flower and fruit but spread efficiently asexually. Each bulbil formed at the leaf axils is capable of forming into a new individual if it falls onto the ground. Underground tubers can also continue to propagate even if the surface parts are destroyed. Its aggressive growth is capable of smothering trees when it climbs over and covers their canopy.

A tree stump, probably smothered by the Zanzibar Yam

Variations of the leaf.

Masses of tubers dug removed from a forest near Bukit Timah Nature Reserve.

A volunteer removing the weed with its tuber attached.

Swollen bulbils at the leaf axils.


Holttum RE. (1964) Plant Life in Malaya. Longmans, Green and Co, London. 254 pp.

Author: Jake
Posted: 2013-01-28 / Modified: 2018-11-27