Description: Fairly slow
growing and usually solitary or forming clumps.
Stem: Globose to short cylindrical, light to dark green, shiny, 8
to 20 cm in diameter. With latex.
Tubercles: Tubercules in spiralled rows, ovoidal to conical up to
1 cm tall, parastichy number 8-13, there is no or few wool in the axil.
Areoles: Rounded with abundant white wool especially the younger
Radial spines: Spreading, 6 - 16, yellowish-white to reddish
brown, becoming grey with age, 5 - 8 mm long.
Central spines: 3 - 5, reddish brown, with dark tips, later grey,
7 - 8 mm long, uppermost longest.
Flowers: Diurnal, very small, inconspicuous, almost concealed
among the tubercles, funnelform, white, greenish, yellowish or creamy
white, 5 - 12 mm long.
Fruits: Club shaped, scarlet-red, 10 - 20 mm long, edible.
Seeds: Small, brown, rough.
Blooming season: Late summer.
Taxomy: M. mammillaris is the
type species of the genus Mammillaria,which itself is
type genus of the tribe Cactaceae of the subfamily
Cactoideae of the Cactaceae.
In fact all cacti should be named "Mammilariaceae", but
the name Cactaceae has been conserved (Nomen
The generic name Mammillaria is also a nomen
conservandum, on one hand against Linné's genus cactus, on the other
hand, against an earlier homonym, the algae species Mammillaria.
Linneé's genus Cactus was soon given up, because it included too many
species unrelated to each other.