Talk:Dildo Key

Dildo Cactus
Searching the Internet comes up with various answers for which species of cactus is the actual dildo cactus: Acanthocereus tetragonus, Cephalocereus millspaughii, Pilosocereus royenii (from an archive of Wikipedia), and Cereus royenii. Which, if any, is the real one? Is dildo cactus perhaps just a colloquial term that can apply to many different species?