You may have the green type of C. usteriana. I have it too, and it look quite similar. A nice and relatively easy plant, very willing to spread.
If it is the one, its full name is Cryptocoryne usteriana var. bogner.
You will have to ID it from flower, though, to be certain for Cryptocoryne (and all other flowering plants).
PS - don't mix up usteriana and aponogetifolia.......they are two different species, though having been considered one species in the past.
If you have true C. aponogetifolia, it will have much more "hammered" leafplate and a more transparent, green colour.
The two other types of C. usteriana will both have burgundy-red underside of leafplate, but look pretty much like this one.