Euphorbia viguieri questions

[kak tus]

Hi all, I have a question on E. viguieri.

It seems that there a few variants - var. capuroniana and var. ankarafantsiensis. What's the major differences between these variants?

I found some photos online of var. capuroniana that branches, but mine has grown for 10 or so years and only started producing a wee new stem recently.

A related question is can they be propagated by cuttings? I.e. For the single-stemmed variant, will they produce branches if the main stem is cut?

Thanks.