Subspecies, varieties, forms and cultivars of plants belonging to the Eriosyce napina group

• Eriosyce napina (Phil.) Katt.: Tiny geophyte, with a solitary sphericalstem slowly growing atop a thick, underground taproot, with a constriction between the stem and the root. Spines: short black, flattened against the stem surface. Distibution Huasco to 15 km south of Freirina.
• Eriosyce napina subs. challensis I.Schaub & Keim: It appears white due to its very woolly areoles and addpressed spines that make it looks like a tiny hairy Epithelantha.
• Eriosyce napina var. duripulpa (F.Ritter) Katt.: Plant with globose stems, small tubercles, and horn-colored spines. Distribution: Vallenar to Huasco.
• Eriosyce napina var. fankhauseri (F.Ritter) Romulski
• Eriosyce napina var. lembckei Katt.: It has small tubercles, stems that sometimes become elongate, and horn-colored spines.
• Eriosyce napina var. mitis (Phil.) Donald & G.D.Rowley: it is a dwarf form with a brown body and short spines pressed flat against the stem.
• Eriosyce napina var. riparia (Mächler & Helmut Walter) Romulski: Distribution: Elqui, east of Trapiche.
• Eriosyce napina var. tenebrica (F.Ritter) Romulski: has dark greyish brown or greenish-black, spherical to flattened stems 2-4(-7) cm in diameter with a conical taproot. Distribution: valley of the Rio Choros.
• Eriosyce napina f. viridis: only differs for the stem colour which is a bright grass green and not a dark tannish-brown. It is (presumably) a nursery selected form, sometime found in the trade.