You have probably found MTS. The latin name is Melanoides tuberculata and there is a cousin that's also found, a 'fawn'. It's also a Melanoides, but I don't remember the rest of the latin name. It's not common. They are essentially the same thing, though. I personally, haven't heard of another type this size and shape. The LFSs call them all sorts of things:
Malayan Burrowing Snail,
Malaysian Livebearing Snail,
Cornucopia Snail,
Horn-of-Plenty Snail,
Philipine Livebearing Snail, etc.....
Go for it.

They are great little guys.