This bell mouth ram's horn snail is native to Maine - yay! - and we have them living in Lake Arrowhead. The shell is a flat spiral, as opposed to the ice cream swirl type of shell. It's an aquatic snail that breathes air and feeds on algae.
We also have a conically spiraled snail that breathes with gills, also living in our lake but it has been introduced. It looks like this: