Good example of the flower
You have a very nice example of p. cerveranum. It is unusual to see a true form of the species, as most growers and nurserymen alike don't have a good grasp on what they need to be looking for. The tooth is rather prominent, mine is a bit larger, and there can be no confusion if you have a plant that is true to its name.
The species does grow in distinct colonies that are true to the type. Unfortunately, greenhouse taxonomy does not lead to accurate conclusions and this species has been wrongly critisized by some.
Take good care of your plant, you have something special there.