Quite a few Hoverflies there Ernie.

Original paper
https://www.pnas.org/doi/epdf/10.1073/pnas.1100628108
Interesting how relatively young our succulent species are.

Matz if I click on your last link I do not have access but if I open it in another tab as if by magic there it is. In DaveW post on the Cacti without soil thread the first and last of the four links cannot be opened unless I do it in another tab.
I don't seem to be capable of copying the links here.

I can understand soil needs some kind of checks but pumice can be used in the building industry and for other things which have nothing to do with horticulture, it's all very strange.

Cider, why do you need a phyto certificate for inert materials?

Yes you do.

Could be Psocoptera Booklouse?

If the individual heads stay small then it looks like it could be Haworthia 'Cassytha' of unknown origin.

Tonight at 7 o'clock in the UK.
https://twitter.com/CactusSucculent/sta ... aN_8g&s=19

It has been nice seeing photos of other peoples versions of this plant. It does look like it would make a good 'wall or rockery' plant but I think it may be to large for most greenhouses, I mean you could get 20x Turbinicarpus in that space