Coryphantha gracilis L. Bremer & A.B. Lau Coryphantha gracilis L. Bremer & A.B. Lau in Cact. Succ. J. (Los Angeles) 49: 71. 1977 sec. Hunt 2016=Escobrittonia gracilis (L. Bremer & A.B. Lau) Doweld in Sukkulenty 3: 17. 2000 syn. sec. Guzmán & al. 2003