Mammillaria octacantha
in Mem. Mus. Par. xvii. (1828) 113.
Family
Cactaceae
Genus
Species
Mammillaria octacantha
Author
DC.
Chinese genus
乳突球属
Chinese name
-
Primary
Accepted
DescriptionEdit description
Central Spines
1-2, straight, erect, brownish, little longer and stouter than the others to 20-25 mm long.
Description
Coryphantha octacanthaSN|3893]]SN|3893]] with olive green body and white and yellow spines, grows prolifically. Plants are solitary or branch basally to form clumps up to 30 or more cm tall. The axils of the tubercles are filled with white wool, with vivid scarlet glands at the base of the groove. The canary-yellow blossoms are very large and showy, the outer segments tinged with scarlet. This striking species is widely cultivated as an ornamental. Given the wide range of this species, it is quite variable and has received numerous names of controversial botanical value.
Tubercles
Loosely arranged, conical, erect, elongated, somewhat 4-sided broad bases, to 25-30 mm long. Axils of tubercles with white wool and with one or two red gland at base of groove. The glands tend to exude a sugary solution when growing. A peculiarity of Coryphantha octacanthaSN|3893]]SN|3893]] is that it may have grooved and grooveless tubercles on the same mature heads at the same time, or may change the form of its growth back and forth from the one to the other.
Flowers
Very large, 4-6 cm in diameter (sometimes 9 cm broad), lemon yellow to straw-colored, with the outer segments tinged with red; perianth-segments glossy, linear-oblong, obtuse, outer ones entire, inner ones serrate and mucronate at apex; filaments orange-red; style red; stigma-lobes 6, linear, yellow.
Stem
Oblong to short cylindrical, solitary or branching basally, deep green to olive green, up to 30 cm tall, and 10(-15) cm in diameter, initially erect but becoming prostrate with age.
Radial Spines
Usually 7-8, awl shaped, thin, rigid, straight, about equal, yellowish with dark tips or horn-colored with black tips, 10-15 mm long.
Fruits
Oblong, to 25 mm long.
Areoles
This species has a common type of spine-areole, white-villous with strong central spines that are somewhat curved and numerous thin radial spines that tend to lie flat against the stem.