I have heard of a large clone/variety of Pinguicula esseriana. I have grown plants labeled as this variety and a few other clones of Pinguicula esseriana. I am still not certain that there are clones with variation in size, as is implied.
I've been able to grow and bloom this species as large plants about 2-1/2" in diameter and smaller plants about one inch in diameter. Both the larger plants and the smaller ones were divisions of the same plants - the only differences were the growing conditions.
Below are some of my plants of this species through the years -->