Hi cana and welcome to the forum!
Some more info:
Order : VIOLALES
Family : CUCURBITACEAE
Genus : Cucumis
Taxon : Cucumis humifructus Stent
Cucumis humifructus (Stent), or the aardvark cucumber as it is known in South Africa is a remarkable plant. Not only is it the only known member of the Cucurbitaceae that fruits underground, but it appears to have an exclusive, symbiotic relationship with the aardvark.
The aardvark locates the underground fruits and uncovers them, tearing the fruit open with its claws and extracting the juicy fruit pulp and seeds with its long, sticky tongue.
After defecating, the aardvark buries its dung. This is an ideal arrangement from the plant's point of view as it ensures that its seed is "planted" in a nutritious medium.
The seeds then germinate during the rainy season.
From the small number of herbarium collections, it appears that the aardvark cucumber is widely distributed over the African continent. Collections have been made in South Africa, Namibia, Zimbabwe, Zambia, Angola, Zaire, Kenya and Ethiopia.
The suspicion is however that the distribution of the aardvark cucumber overlaps with that of the aardvark and that the plant will be found wherever there are suitable aardvark habitats.
In South Africa, where the aardvark has been classified as a vulnerable species,
aardvark cucumbers are presently regarded as rare and endangered (so IMHO think it will be difficult to obtain seeds

)
Maybe you should contact the Botanical Society of South Africa
here
Or the South African National Biodiversity Institute
here
I'm sure someone there will be able to assist you!
Please let us now if you find out anything
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