Cissus quadrangularis is pretty common but does not resemble a Hoya and is in the same family as grapes, the Vitaceae. The cucumbers are in the family Cucurbitaceae and there are many species that have tuberous roots and send up an annual climbing vine. Hoyas are totally unrelated and belong in the subfamiuly Asclepiadoideae of the family Apocynaceae.

Try looking up Kedrostis africana and see if that matches your plant. Sometimes rare plant sellers offer the Gemsbok cucumber from Namibia but it is not a climber.

Mike

Here is a link that might be useful: Succulent Cucumber vines

Nope. Neither of those. I will take a picture of it tomorrow and post it and maybe someone will know it by another name.

I love hoyas and collect all I can find, so when I saw it with the hoyas, I thought it was one, but the owner said no...but a relative.

Thanks for your input.

If the plant truly is related to Hoya it may be a Dischidia species. Trade or common names can be confusing so I guess we can assume that the reference to cucumbers is a superficial one.
Check the Dischidia photo page to see if any resemble your plant. The photo will definitely help.

Mike

Here is a link that might be useful: Dischidia.com

Is it this? It is in the cucumber family, I think. Looks sorta hoya like.

Here is a link that might be useful: Xerosicyos danguyi