Snails?

[gwhite314]

Does anybody know of a way to tell the difference between a collonista snail and a sundial snail? I have been staring at the on-line photos and comparing them to the snails I am pulling from my tank. I can't determine which they are.

 

[roka64]

The sundials have a "trap door cover", sorry I can't remember and tend to have a "narrower/flatter" shell. The collonista snail has a rounder shell and I *think* they have the "trap door cover" as well.
http://www.aquaticcommunity.com/SwSnails/Collonista.php