Origin and Habitat: Epithelantha micromerisSN|6936]]SN|6936]] var. rufispina is found in abundance from Parras de la Fuente to south of Saltillo in the state of Coahuila, Mexico.
Habitat: It grows in the shelter of bushes and grasses and is a bit difficult to spot in its half- hidden location.

• Epithelantha micromeris var. rufispina (Bravo) Backeb.
• Epithelantha greggii var. rufispina (Bravo) Backeb.
• Epithelantha rufispina Bravo

• 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: Epithelantha micromerisSN|6936]]SN|6936]] var. rufispina is a minute globular button cactus, becoming somewhat elongated when old. A dainty plant, and an easy one to handle. The short spines of this little cactus are appressed to its body and so do not puncture your hands.
Stem: Solitary, up to 10 cm tall, but at times has offsets at the base. The appressed apex contains many reddish spines. The stem becomes quite dehydrated during drought, but fills out quickly.
Spines: 30-40 all radials, greyish-white in young specimens, turning to a grey-reddish or brownish tinge in adult plants crown, while the rest of the spines on the body of the plant are greyish.
Flowers: Small cream-pink coloured, emerging from the wool at the apex.
Blooming season Flowers start open from April in succession over a longer time later in summer.
Fruits: Oblong to clavate, red, edible, referred to as "chilitos" or little chili peppers. Their taste is tart, however, and not peppery.
Taxonomy: Dr. Helia Bravo first described this cactus in 1951 as Epithelantha rufispinaSN|12633]]SN|12633]]. Backeberg in 1954 found it to be a variety of Epithelantha micromerisSN|6936]]SN|6936]] and called it E. micromeris var. rufispina.

Bibliography: Major references and further lectures
1) Curt Backeberg “Die Cactaceae: Handbuch der Kakteenkunde” Gustav Fischer Verlag, Stuttgart New York 1982–1985
2) Curt Backeberg "Das Kakteenlexikon", 1966
3) Saguaroland Bulletin, Volumi 26-27, page 40, Arizona Cactus and Native Flora Society, 1972

Cultivation and Propagation: Although regarded as a choice and difficult plant in cultivation it is relatively easy. Needs a soil mix particularly well draining (rot prone). Water sparingly and keep perfectly dry in winter. Hardy to -7°C
Sun Exposure: Light shade to full sun.
Propagation: Seeds, offsets.