This plant is native to South Africa; Transvaal and Natal. It has been known since1905.
I have 'lost' this plant a number of times. It is a particularly sensitive tuberous ceropegia. In the winter it must be absolutely dry in my conditions. I had one tuber a few years ago that started to sprout in the greenhouse in late winter, It was a fairly large tuber, more than 2 inches across, and there was a lot of growth. The pot looked as if there were filled with a bouquet of stems and leaves. It bloomed nicely and when the weather warmed I hung the basket outside in real weather. Sometime later that summer I noticed that the plant looked a little collapsed, feeling around for the tuber I discovered that it had rotted away. Each of the stems had started to thicken at the base and were apparently forming new tubers. What I didn't do then was remove the thickening stems to new pots where they could grow in a dryer more protected atmosphere. I didn't, and of course, they suffered in the remaining summer rains and wasted away before fall.
The picture above shows some flowers at just about life-size. The leaves are succulent and very firm, the tuber looks like the tubers for rendallii and woodii.