Family:
Cactaceae (Cactus
Family)
Scientific name: Mammillaria
thornberi Orcutt
Place of publication: W. Amer. Sci. 12:161. 1902
Origin: These cacti are typically found
in Arizona and
Mexico (Sonora)
Habitat: Sonoran desert scrub, valley floors, silty or
sandy soils; 10-600 m. . It will grow only where it is shaded from the
full sun. This can be under shrubs and frequently at the base of Opuntias, where the germinating seeds find added protection provided by
the numerous fallen opuntia joints.
Common Names include: Thornber's Fishhook Cactus,
Thornber's nipple cactus, clustered Fishhook Cactus, clustered
pincushion, slender pincushion, organ pipe.
Etymology: Named after Prof. John Thornber (1872-1962)
US- American botanist at the university of Arizona
Conservation status: Listed in
CITES appendix 2.
Synonyms:
- Mammillaria fasciculata Britton & Rose 1923,
misapplied, not Engelmann ex B.D. Jackson 1895 (see
Echinocereus fasciculatus)
- Neomammillaria fasciculata
- Cactus fasciculatus
- Ebnerella fasciculata (Britton & Rose) Buxbaum 1951
- Chilita fasciculata (Britton & Rose) Buxbaum 1954
- Mammillaria yaquensis R.T. Craig 1945
- Ebnerella yaquensis (R.T. Craig) Buxbaum 1951
- Chilita yaquensis (R.T. Craig) Buxbaum 1954
- Mammillaria thornberi ssp. yaquensis (R.T. Craig)
D.R. Hunt 1997
The epithet fasciculata was long
misapplied to Mammillaria thornberi.
It correctly
pertains to
Echinocereus fasciculatus (Engelmann) L. D. Benson.
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Description: M. thornberi is a
small cactus
with slender stems, that likes to cluster from
the base, forming nice
clumps or families. The particularity of this species is that every
branch will form an independent root system, the connections of which to
the rest of clone are
ephemeral, resulting in dense clumps of independently rooted stems.
Roots: Diffuse, upper portion not enlarged.
Stems: Slender, cylindrical, often dull purplish green, 4.5-10 cm
tall (but sometime 30 cm high), 2-3.5 cm in diameter, tapered at base,
firm, lateral joints easily detached from the body.
Tubercles: Flabby, purplish green, short conical to cylindrical.
5-9 × 5-9 mm;
axils appearing naked or slightly woolly;
cortex and
pith not
mucilaginous;
latex absent.
Parastichy number: 5-8
Spines: Usually 14-22 per areole, whitish to yellowish near base,
pale reddish brown to nearly black toward tips, glabrous; They do not
hide the surface of the stem completely.
Radial spines: 13-21 per areole, whitish, with reduced dark tips
relative to central spines, bristlelike, 5-9 mm long, stiff.
Central spines: Small, fish-hooked, usually 1 (or sometime 2 or 3)
per areole, porrect, often more elongated, darker, 9-18 mm long.
Subcentral spines: 0(-3) per areole,
adaxial to central spines, more or less transitional to radial
spines.
Flowers: Broadly funnel-form, light
pink on the outside and a deeper lavender pink in the center, with a
white star shape appearance from a distance, due to the contrast of colors, 1.5-3 long and 1-2.5 cm large.
The outermost
tepal margins are densely short-fringed.
Blooming season (In Europe): Apr-May, July-Aug.
Fruits: Prominent, bright red, obovoid to nearly clavate, 7-15 ×
4-7 mm, juicy only in fruit walls;
floral remnants persistent. Fruiting in Oct-Nov, Feb-Mar.
Seeds: Black, 0.9-1.1 × 0.8-1.1 × 0.7 mm, pitted.
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The subspecies 'thornberi' has thicker stems,
2,5 cm wide and tapered at the base, with 15-20 radial spines. The radial
spines are not distinctly pubescent. It o,ccurs in Arizona and Sonora.
The subspecies 'yaquensis' has more fragile stems at 1,5 cm thick
and 7 cm long, with 18-19 minute, soft, and hairy radial spines. It is
endemic to Sonora.
Cultivation: This plant
blooms easily and needs lots of light. Use a pot with good drainage and a
very porous
mineral-based potting mix. Potted plants are quite
wet-sensitive, especially in light of its small root
system. Water sparingly during the
growing season, letting soil dry in
between to prevent root rot. Keep very dry in
winter. Feed
with a high potassium fertilizer in summer.
Usually it is recommended to
overwinter this plant in a bright and warm greenhouse
at at least
8-10° C , but it has proved to be quite
frost resistant
(if kept dry, it
is hardy as low as -7° C).
A resting period in winter and strong light are necessary so that it can
flower properly. Plants will offset readily, and
dense clumps can be produced in a very few years.
Propagation: Through seeds and
cuttings. |