I did kind of figure it was a toadstool, however is it a particular kind? I've seen one with green polyps. This one looks more like the long polyp snow toadstool except the polyps are bright green and the stalks seem unusually thick, which is why I made the comment it looks like a gonipora tree. I would not consider this a standard toadstool, which is why I was hoping someone could ID the type (if it has a name) and origin and if it's available in the US.