Just can't make up our minds about this. The species is believed extinct which in turn leaves one to believe there is no way of ever confirming or denying anything with respect to just how variable the species would have been. Nor what differences would have appeared in seed grown plants. E. 'Vincent Catto' was described in 2009. Who is to say there wasn't a self pollination done on plants that were at the time believed to be this species, or where or how both this and the European plant aren't in fact forms of the species long lost in habitat. Guess there's just too much speculation for us so really don't care what name people use.
Heads around 3cm, slow growing and clumping. Careful summer watering.