• Epithelantha greggii subs. potosina D.Donati & Zanov.

• Epithelantha micromeris (Engelm.) F.A.C.Weber in Bois
• Cactus micromeris (Engelm.) Kuntze
• Cephalomamillaria micromeris (Engelm.) Frič
• Echinocactus micromeris (Engelm.) F.A.C.Weber in Bois
• Mammillaria micromeris Engelm.
• Epithelantha micromeris var. caespitosa Y.Itô
• Epithelantha micromeris f. cristata hort.
• Epithelantha micromeris var. longispina Y.Itô
• Epithelantha micromeris var. neomexicana n.n.
• Epithelantha neomexicana n.n.
• Epithelantha micromeris var. rufispina (Bravo) Backeb.
• Epithelantha greggii var. rufispina (Bravo) Backeb.
• Epithelantha rufispina Bravo
• Epithelantha micromeris var. texensis n.n.
• Epithelantha micromeris var. texensis f. cristata hort.
• Epithelantha micromeris var. typica Croizat

• Epithelantha micromeris var. dickisoniae hort.
• Epithelantha dickisoniae
• Epithelantha greggii var. dikisoniae

• Epithelantha micromeris subs. greggii (Engelm.) N.P.Taylor
• Cactus micromeris var. greggii (Engelm.) J.M.Coult.
• Cephalomamillaria greggii var. greggii (Engelm.) Frič
• Cephalomamillaria micromeris var. greggii cv. Gray Herb. CardCat., Issue 114 (Engelm.) Frič
• Epithelantha greggii (Engelm.) Orcutt
• Epithelantha micromeris var. greggii (Engelm.) Y.Itô
• Mammillaria greggii (Engelm.) Saff.
• Mammillaria micromeris var. greggii Engelm.
• Epithelantha greggii subs. potosina D.Donati & Zanov.
• Epithelantha micromeris var. densispina (Bravo) Backeb.
• Epithelantha densispina Bravo
• Epithelantha greggii var. densispina (Bravo) Backeb.

• Epithelantha micromeris subs. greggii f. cristata
• Epithelantha greggii f. cristata

• Epithelantha micromeris subs. pachyrhiza (W.T.Marshall) N.P.Taylor
• Epithelantha micromeris var. pachyrhiza W.T.Marshall
• Epithelantha pachyrhiza (W.T.Marshall) Backeb.
• Epithelantha micromeris f. elongata (Backeb.) Bravo
• Epithelantha pachyrhiza subs. elongata (Backeb.) D.Donati & Zanov.
• Epithelantha pachyrhiza var. elongata Backeb.

• Epithelantha micromeris subs. polycephala (Backeb.) Glass
• Epithelantha greggii subs. polycephala (Backeb.) D.Donati & Zanov.
• Epithelantha micromeris var. polycephala (Backeb.) Glass & R.A.Foster
• Epithelantha polycephala Backeb.

• Epithelantha micromeris subs. unguispina (Boed.) N.P.Taylor
• Epithelantha micromeris var. unguispina (Boed.) Backeb.
• Epithelantha unguispina (Boed.) D.Donati & Zanov.
• Mammillaria micromeris var. unguispina Boed.
• Epithelantha spinosior
• Epithelantha unguispina subs. huastecana D.Donati & Zanov.

Description: Distribution: San Luis Potosí (Mexico Northeast, Mexico, Northern America)

Type Locality: Mpio. Guadalcazar, East of Charco Blanco