I don't know what this is called. It looked vicious though.

Very unusual. It does look vicious doesn't it? I wouldn't want to shimmy up that trunk.

ouch

It's very unusual. Are those blue flowers growing on it ?

No Hywel, I think that it's a mallow behind it. Sorry, I should have got a better shot of the rest of the plant.

Is this a type of Pachypodium perhaps??

I'm not sure about that Gilli. I looked up Pachypodium and they looked spiny like a cactus and this one above had thorns, very silmilar to roses.