Just found this guy crusing on the sand. I do have collonista snails, but this guy is way too big for a collonista. Any idea what it is. FYI, I haven't added anything to my tank in ages, with the exception or six trochus snails a week or so ago....and this guy wasn't part of that package.
![IMG_0276_zps8166e21e.jpg](http://i419.photobucket.com/albums/pp271/psh54/IMG_0276_zps8166e21e.jpg)