English: Petalifera petalifera from Turkey. At the beginning they were colourless, but as they grazed on the walls of the aquarium it got browner. See also :Image:PetaliferaPetaliferaSeaSlugB.jpg.
I requested release under the GNU public license from the creator Baki Yokeş. I still have the original email. I requested permission from the creator to use it under the GNU license, and his repsonse was Yes you can use it, and if you need photos of other species just let me know. I have quite a large photo collection of marine invertebrates from the Mediterranean, about 750 species, mainly molluscan shells (about 450), and also some Indo-pacific immigrants. Some of them are new to science and await for publication. I think you cannot get their photos from anyone else :)). On request i can forward the original email to another admin for verification. Please contact me on my talk page if needed -- Chris 73