Accepted Scientific Name: Epithelantha micromeris subs. unguispina (Boed.) N.P.Taylor
Cactaceae Consensus Init. . 5: 12. 1998
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Epithelantha micromeris var. unguispina (Epithelantha micromeris subs. unguispina) Photo by: Valentino Vallicelli
The plant above is a 27 year-old specimen. Ex Prof. Lodi collection (Italy Bologna Botanical Garden )
Origin and Habitat: Monterrey and adjacent areas, Nuevo Leon, North-East Mexico
Altitude: Around 1200 metres above sea level.
Habitat: It grows nested on crevices in step calcareous cliffs together with Mammillaria melanocentraSN|10031]]SN|10031]].
Synonyms:
See all synonyms of Epithelantha micromeris
Description: Epithelantha micromeris subs. unguispina (best known under its old name Epithelantha unguispina) is similar to the type species but usually a little larger and free clustering with a distinct, slightly long projecting black-tipped central spines, also the pink flowers are larger than the others.
Habit: It is a miniature globose cactus, erect, clumping over time, not deep-seated in substrate, appearing ashy grey and relatively rough in general aspect.
Stem: Unsegmented, globular, up to 8 cm tall and 6(-7) cm in diameter, often flat-topped with a depressed centre, 3-6 cm in diameter, occasionally more; surface not completely obscured by spines; cortex and pith are not mucilaginous.
Tubercles:** Numerous, not confluent into ribs, hemispheric or short cylindric, very small, ca. 1-3 mm; arranged in tight spirals around the plant.
Areoles: Small at tips of tubercles, 1 mm long, nearly circular, elliptic when distended by flower or fruit, slightly woolly when young, copiously woolly only at sexually mature stem apex; areolar glands absent;
Central spine: One, conspicuously longer than in other subspecies, mostly 4-5mm long (occasianally up to 20 mm), downwards curved and often black-tipped.
Radial spines: (16-)18-22(-24) white to ashy grey white and flattened, somewhat pectinate, appressed on sides of stems, straight, terete, slender, innocuous 1-2,5 mm long.
Roots: Diffuse.
Flower: Small but larger than the others subspecies, pale to deep pink, funnelform diurnal, borne at adaxial margins of spine clusters in the plant top.
Blooming season: Flowers late winter to spring. Autosterile. It is very floriferous.
Fruits: Indehiscent, bright red, thin narrowly cylindric, 3-20 × 2-3(-5) mm, weakly succulent, soon drying and papery, smooth, spineless; pulp absent; floral remnant deciduous.
Remarks:*** Its fruit are known in mexico as "chilitos."
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Subspecies, varieties, forms and cultivars of plants belonging to the Epithelantha micromeris group
Epithelantha micromeris (Engelm.) F.A.C.Weber in Bois: Miniature globose cactus, unbranched or in small clumps. Produces small pink flowers followed by attractive red fruits . Spines are white or greysh, innocuous and appressed on sides of stems.
Epithelantha micromeris f. cristata hort.: This is a miniature cactus that makes a nice and tangled cluster of fine crests. The stem surface is completely obscured by small pectinated ashy-grey to white spines.
Epithelantha micromeris var. dickisoniae hort.: Minute clustering cactus of doubtful status (but common in cultivation), it shows similarities with Epithelantha micromeris subsp. polycephala and Epithelantha pachyrhiza. Spines are whitish turning to a brownish tinge in adult plant's crown. Roots: Tuberose.
Epithelantha micromeris f. elongata (Backeb.) Bravo: It has elongated stems and a thick tap-root. It is intermediate between E. micromeris and E. pachyrhiza. Distribution: Ramos Arispe, Coahuila, Mexico.
Epithelantha micromeris subs. greggii (Engelm.) N.P.Taylor: This subspecies has a rough, somewhat bristly appearance with iIndividual stems up to 5 cm or more in diameter,. Spines are chalky white to reddish brown. Distribution: Northern Mexico, especially Saltillo, Coahuila.
Epithelantha micromeris subs. greggii f. cristata: crested form.
Epithelantha micromeris var. neomexicana n.n.: This is the population found in New Mexico (USA) but this taxon is not easily recognizable from other Epitelantha micromeris (if not the same identical plant)
Epithelantha micromeris subs. pachyrhiza (W.T.Marshall) N.P.Taylor: It has tuberousroots and a stem only partly obscured by the white to orange-tan spines; Distribution: Strictly endemic of southeast and northeast of Saltillo.
Epithelantha micromeris subs. pachyrhiza f. cristata
Epithelantha micromeris subs. polycephala (Backeb.) Glass: Clustering miniature cactus; an old plant may have more than 100 heads, and be 10 cm of diameter. Spines are grey/whitish, pastel or ocre. Distribution: it occurs in a limited area of Coahuila.
Epithelantha micromeris var. rufispina (Bravo) Backeb.: Minute globular cactus, becoming somewhat elongated when old. the spines are numerose up to 40 whitish all radials, turning to a grey-reddish or brownish tinge in adult plants crown. The spine base is reddish.
- Epithelantha micromeris var. texensis n.n.: This is the population found in Texas (USA) but this taxon is not easily recognizable from other Epitelantha micromeris (if not the same identical plant)
Epithelantha micromeris var. texensis f. cristata hort.: Crested form.
Epithelantha micromeris subs. unguispina (Boed.) N.P.Taylor: It is a little larger than the standard form. Stem globular, up to 6 cm, often clumping over time. It generally has a small projecting black-tipped central spine, 4-5mm long. Origin: Near Monterrey, Nuevo Leon, south into San Luis Potosi.
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Bibliography: Major references and further lectures
1) Edward Anderson “The Cactus family” Timber Press, Incorporated, 2001
2) James Cullen, Sabina G. Knees, H. Suzanne Cubey "The European Garden Flora Flowering Plants: A Manual for the Identification of Plants Cultivated in Europe, Both Out-of-Doors and Under Glass" Cambridge University Press, 11/Aug/2011
1) David R Hunt; Nigel P Taylor; Graham Charles; International Cactaceae Systematics Group. "The New Cactus Lexicon" dh books, 2006
2) Sean Hogan "Flora: a gardener's encyclopedia" Volume 1 Timber Press (Portland, Or.) 2003
3) Cactus and Succulent Journal (US) 50: 186, f 5 1978
4) Hiroshi Hirao “Colour encyclopaedia of cacti” Japan 1979 (Japanese language and script)
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Epithelantha micromeris var. unguispina (Epithelantha micromeris subs. unguispina) Photo by: Prof. Ilham Alakbarov
VM635 Castaños, Mexico (Epithelantha micromeris subs. unguispina) Photo by: Valentino Vallicelli
Epithelantha micromeris var. unguispina (Epithelantha micromeris subs. unguispina) Photo by: Cactus Art
Epithelantha micromeris var. unguispina (Epithelantha micromeris subs. unguispina) Photo by: Valentino Vallicelli
Epithelantha micromeris var. unguispina (Epithelantha micromeris subs. unguispina) Photo by: Valentino Vallicelli
Epithelantha micromeris var. unguispina (Epithelantha micromeris subs. unguispina) Photo by: Valentino Vallicelli
Epithelantha micromeris var. unguispina (Epithelantha micromeris subs. unguispina) Photo by: Cactus Art
Epithelantha micromeris var. unguispina (Epithelantha micromeris subs. unguispina) Photo by: Cactus ArtCultivation and Propagation: Although regarded as a choice and difficult plant, in cultivation it is relatively easy, but very slow growing. These plants need very coarse potting soil that drains well (rot prone). Waterings should be rather infrequent, to keep the plant compact and not become excessively elongated or unnatural in appearance.
Frost Tolerance: Depending on the variety, it will take -5° C (or less) (Temperature Zone: USDA 8-11)
Sun Exposure: It requires strong sun to part sun to develop good spinal growth, but some summer shade in the hottest hours of the day is beneficial. Assure a good ventilation.
Propagation: It can be reproduced both by seeds and cuttings, but it is often grafted because difficult and slow to grow on its own roots. Older specimens shoot tillers from under tubercles, so they can be grafted, which is a much easier way of propagation than sowing. Young seedlings are tiny and they need several years to reach adult size, and require careful watering.
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by Cactus Art