It's definitely an unnerving feeling to see one go up the python. And where there's one....there's usually another one or two or three. They do stay totally under the gravel thank goodness. I had the page bookmarked as a favorite but we recently got new computers so all was lost. I still continue to search and see if I can dig the picture up. There's no mistaking it for a leech or anything else. The picture is totally accurate to what I had found.