Epithelantha Micromeris, a cactus from southern North America.
5 seeds: sown 20-02-2014; three germinated between 13 and 20 days. I decided not on hang on for the others, and repotted these three with my two Cintia Knizei 08-04-2014.
Picture taken 18-04-2014. The Epithelantha are the three seedlings on the right.