Cactus / retusus

I bought seeds of Ariocarpus retusus cv mitsibo (tri-fingers) and sowed on 11th August 2005.
Several young seedlings were grafted.
This is one of them.
It is told that the character of the tri-fingers will appear when the plant was a mature age.
I have waited long time for the change but it seems no hope.
The plant is in flower in this season every year.