I got some moss about 2-3 months ago and I happened to get some baby snails along with it. There are several different kinds snails some I believe are ramshorn snail pictured here
and the rest are these guys
which I am unsure about.
No, the ones on the bottom are not MTS. I'm not sure what they are, but I have had them too. They are much smaller than MTS, and have a different shell shape.
MTS come in a variety of shell shapes and patterns... I actually suspect that several Thiaridae snails are sold as MTS rather than just Melanoides tuberculata (which are in fact, within their own genus in that family).