Pictured here is a photograph of my husband's butterfly birthmark. I recall clipping a piece from a women's magazine (probably "Woman's Day" or "Family Circle") in the 70s that I picked up at the checkout lane at the local grocery market. It was a cute poem that gave superstitious meanings for various locations of moles or birthmarks on the body. I actually framed it and hung it in my bathroom as a conversation piece. I don't remember whatever became of it.
I'm considering gathering some information about birthmarks and folklore to put together in a fun and interesting article sometime in the future. Meanwhile I hope you will tell about your birthmarks and also upload photos of your birthmarks.