Obviously, I don't know the story or the etymology behind the English expression. Perhaps an English philologist or an English speaker can help with that.
Acant is a name used in Catalonia. It is unusual, as most of the nature names, but it is not unheard. For instance, there is an actor named Acant, Acant Canet (and I met another one in person).
Before the new Spanish naming law (and in some small towns, even after it), many people had a hard time trying to register nature words as a names, so they usually registered a non-related name for the child, who went always and exclusively by another name (a nature word); that is the case, for instance, of a girl named Nit ("night"), registered as Maria. This situation disguises the real use of nature names.