SB544 , Mitla, Oxaca, Mexico.
thickly covered with tawny wool and rounded, flattened above (retuse)
Spines pectinated pale-yellow/white with darker tips later turning grey.
Cultivation: In culture C. retusa is
without problems, but it grows slowly. It
does best in slight shade, but does well in full sun,
too. It is sensitive to over-watering (rot
prone), and needs a very porous soil with good
It flowers quite early, but needs about 8-12 years to reach
its typical, definite
aspect. It tolerates fairly low temperatures as long as it
is kept dry (hardy to -5° C or less, for short
periods of time).
Propagation: Propagation is
Scientific name: Coryphantha
retusa (Pfeiff.) Britt. &
In: Cactaceae 438,1923
Origin: Mexico (Oaxaca,
Habitat: Open grassland on
Conservation status: Listed in
CITES appendix 2.
Etymology: The species epithet "retusa" comes from
Latin "retusus", past participle of "retundere", to beat
back : "re-" + "tundere" to beat for the retuse tubrcles tip [ rounded
or obtuse with a central shallow indentation ]
- Melocactus mammillariaeformis
In: Allg. Gartenz. 4:192,1836
- Mammillaria cephalophora
In: Cact. Hort. Dyck 1849:137
- Echinocactus cephalophorus
In: Alg. Gartenz.21: 102,1853
- Cactus cephalophorus (Salm-Dick)
In: Rev. Gen.Pl.1:260, 1891
- Coryphantha malleospina
In: An. Inst. Biol. Mex. 25:526,
- Coryphantha retusa var.
melleospina (Bravo) Bravo
In: Cact. Suc. Mex.27:17, 1982
- Cactus retusus (Pfeiff.)
- Mammillaria retusa
Description: Generally not
offsetting, rarely clumping when old.
Stem: Depressed spherical 5-10 cm in diameter, 3-8 cm tall, with
narrowed base and very woolly apex. Epidermis dark green or
Tubercles: Conical rounded, flattened above (retuse), unequally
swollen, up to 8 mm tall with abundant wool in the axil and furrow when
parastichy arrangement: 8-13 (13-21).
Areoles: Oblong 4 x 2 mm wide.
Central spines: Absent. (very rarely has 1 central spine )
Radial spines: 6 – 12 ( to 15) pectinated, 3-4 of them on each
side, strong subulate, flattened, curved to the body and slightly
downward, radiating the lowest on straight downwards, the 3-5 in the
upper part of the areoles thinner needle like. All 14-20 mm long,
pale-yellow/white with darker tips later turning grey.
Flowers: Bell shaped, central, up to 4 cm cream or yellow, perianth
segment lanceolate,oblong, acute, filaments reddish, anthers yellow,
stigma and lobes whitish-yellow.
Fruit: Olive green, juicy, oblong 30 x 9 mm.