cochleata
 

I want to buy an octopus orchid. I think it's also called a clamshell. I bought one a years ago and it was marked Encyclia cochleata. After a few years it died, and I want to try it again, because I loved it so much. But now that I'm looking for one I see them marked as Prosthechea cochleata.
My question is did they change the name or is it two different orchids? If it is two different orchids, what is the difference?

Same orchid, just reclassified

And if you look more you might even find that was called Anacheilium cochleatum in the past as well.

Sometimes old names were because two different people discovered and named the same orchid. Or they disagreed that they were the same species. Eventually that gets worked out.

Other times it was all "agreed," but then the taxonomists uncover a reason to change the name. Sometimes this is based on new knowledge or the structure of the flower of the plant, or, and this is becoming much more common, on an analysis of the the DNA.