Habit: Generally erect (decumbent or prostrate), branched or not, branches 0--9(50).
Stem: 5--30 cm, [1.8]3--7.5[20] cm diam, spheric to cylindric [or obconic], firm to soft, not regularly segmented; ribs 0, tubercles prominent, conic to cylindric, not grooved.
Spines: [2]14--64(90) per areole, < 2 mm diam, needle-like [to hair-like or bristle-like], glabrous [or plumose], straight or hooked [or curved to crinkly]; central spines 1--4 [0--many] per areole, generally hooked.
Flower: lateral, in axils of tubercles, 1--5 [7.5] cm diam; perianth cream to white, pink, purple, or lavender; ovary glabrous, spines 0, scales 0.
Fruit: club-shaped or cylindric to ovoid [or barrel-shaped], indehiscent, generally red, spines 0.
Seed: 0.8--1.5 mm, generally shiny, generally pitted or raised-netted, black [brown to +- red or +- yellow], occasionally with aril.
Species In Genus: 150 species: North America.
Etymology: (Latin: nipple)
Jepson eFlora Author: Bruce D. Parfitt
Reference: Hunt 1984 Bradleya 2:65--96; Hunt 1985 Bradleya 3:53--66; Hunt 1987 Bradleya 5:17--48
Index of California Plant Names (ICPN; linked via the Jepson Online Interchange)Key to Mammillaria
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