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Dioscorea strydomiana Wilkin is also commonly known as Ebutsini wild yam and Strydom's wild yam. Dr. Paul Wilkin, an international Dioscorea expert, named this species as ‘the world’s most threatened yam’ and is one of the 100 most threatened species.

Description
This species was discovered by Gerhard Strydom and Johan Hurter, when they worked for the Mpumalanga Parks Board and this species was named after Gerhard Strydom. Dioscorea strydomiana is currently on the IUCN Red List, where it is listed as “Critically Endangered”. IUCN Red List an indicator of health of the world’s biodiversity.

D. strydomiana is not a typical yam, it is a shrub and has a ‘lumpy’ wooden tuber/root above the ground. This species is different from the other Dioscorea species, since the stems of the plant are not twining. The tuber can grow up to a 1m in height and diameter and the shrub can be 1.5m tall. The outer layer of the tuber is corky with many grooves. This species is very long-lived and slow growing, although it produces many seeds only very few actually germinate successfully.

This species is dioecious, which means the male and female inflorescence are born on separate plants. The fruits are dry capsules that release a large, winged seeds, which are mid- to dark brown. Both male and female flowers are small (<10mm in diameter) and appear in the late spring to summer. Since this plant is dioecious, it relies on cross pollination for fertilization to succeed.

The genus Dioscorea name comes from Dioscorides, a Greek physician and botanist and this genus has about 600 species, with many species to still discovered. The phylogenetic tree of Dioscorea is very diverse in their morphology and used sequence data to look the different morphological traits.

Distribution
Dioscorea strydomiana is a new species of yam local to the Mpumalanga in South Africa.

Habitat
It grows in an open woodland where there is understory with a lot of grass “on a steep, rocky, south-east to south-south-east facing slopes”.

Medicinal Use
This species is said to have medicinal properties to help treat cancer when used with another species of Dioscorea. The related species D. elephantipes and D. sylvantica — have high steroidal compound levels, which D. strydomiana might have used to treat inflammation, e.g. arthritis or to help with healing. In South Africa, this plant is seen as a cure for cancer in their traditional medicines, although there is no evidence of their healing properties.

Conservation Status
There are only two populations of these wild yams with only around 200 left.

The major threat to this species is due to the collection for medicinal use and that it is very a slow growing species as well. Since they grow above ground, there is an over-exploitation by collectors taking large parts of the tuber, which contributes largely to the death of the plant. Through a survey done, found that over 89 percent of the wild yam population had harvesting scars.

A study was done by Mattana et al. (2019) found that D. strydomiana had poor seed lot quality that may indicate the difficulties in reproduction from the seed, therefore we need to look more into the conservation of this threatened yam species.

Action Required
Need to find a strategy for sustainable use of the wild yam and set up ex situ or off-site conservation collections.