Accepted Scientific Name: Mammillaria albilanata subs. oaxacana D.R.Hunt
Mammillaria Postscripts 6: 9 (1997), nom. nov. (Replaced synonym:Cactaceae Mammillaria ignota Repp.)
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Mammillaria ignota (Mammillaria albilanata subs. oaxacana) Photo by: Valentino Vallicelli
Origin and Habitat: Mammillaria albilanataSN|15150]]SN|15150]] subs. oaxacana is endemic of the Tehuacán-Cuicatlán Valley in the state of Oaxaca (Cuicatlán, Huajuapan, Nochixtlán, Teotitlán departments), Mexico.
Altitude range: 800-2550 metres above sea level.
Habitat and ecology: This species grows on limestone rocks, in humus soil between spare overgrowth in tropical deciduous forest, xerophilous scrub, oak )Quercus) forest, and secondary vegetation together with Ferocactus macrodiscusSN|4317]]SN|4317]].
Synonyms:
See all synonyms of Mammillaria albilanata
Common Names include:
SPANISH (Español): Cabeza blanca
Description: Mammillaria albilanataSN|15150]]SN|15150]] subs. oaxacana is a usually solitary cactus species, with flat stems. It protects itself from the sun by an extremely dense profusion of white spines and wool so that the epidermis is almost completely concealed.
Taxonomy note: Mammillaria albilanataSN|15150]]SN|15150]] subs. oaxacana is a new name proposed by Hunt (1997) which replaces M. ignota Repp. (1987), that is a homonym of another previously published name (M. ignota Lawrence in Loudon, 1841).
Stem: Simple, depressed globose to cylindrical, sunken apically, covered with spines and white wool, 3–7 cm high and 4–10 cm in diameter. With latex.
Tubercles: Tubercles are spirally arranged, short-conical to conical, firm, 8 - 10 mm long and 4-5 mm in diameter at base. Axil with abundant white wool.
Roots: Fibrous.
Radial spines: 20-22 (-27), needle-like, somewhat bristly, glassy white to white, smooth, straight, somewhat radiating, horizontal, 4 mm long.
Central spines: 1- 4(-6), mostly 4, needle-like, firmer than the radials, ascending,divergent, straight , rigid, non-uncinate, the lowest is the longest, 4-7 mm long, glassy white, white to yellowish with short brown tips.
Flowers: Funnel shaped carmine-pink, cherry red to pink, 12-18 mm long, stigmas greenish.
Blooming season: From early March to June.
Fruits: Red, ripens 6-8 months after flowering, 10-20 mm long and 3-4 mm in diameter.
Phenology: Flowering between February and May. Fruiting between May and July.
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Subspecies, varieties, forms and cultivars of plants belonging to the Mammillaria albilanata group
Mammillaria albilanata Backeb.: (ssp. albilanata) has deep carmine flowers, 15-20 radial spines. Distribution: Guerrero.
Mammillaria albilanata subs. oaxacana D.R.Hunt: has 20-22(-27) white radial spines to 4 mm long. 1-4(-6) radials 4-7 mm long, glassy white with short brown tips. Distribution: Tehuacán-Cuicatlán Valley, Oaxaca, Mexico.
Mammillaria albilanata subs. reppenhagenii (D.R.Hunt) D.R.Hunt: has carmine flowers with lighter margins, 19-26 radials. Distribution: Colima.
- Mammillaria albilanata subs. tegelbergiana (H.E.Gates ex G.E.Linds.) D.R.Hunt: has purplish pink flowers, 18-24 radials. Distribution: Chiapas.
Mammillaria noureddineana Repp.: stem globose to cylindrical, apex covered with white wool and spines. Radial spine: 15-20, central spine: 4 -6 glassy white with brownish tip. Flowers carmine. Distribution: Oaxaca, between San Pablo villa de Mitla and Ayutla. Altitude 1900 - 2000 m.
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Bibliography: Major references and further lectures
1) Kakteen und andere Sukkulenten, Volume 56, 2005
2) Salvador Arias Montes, Susana Gama-López, L. Ulises Guzmán-Cruz “Flora del valle de Tehuacán-Cuicatlán: Cactaceae Juss”, Part 95, Universidad Nacional Autónoma de México, Instituto de Biología, 2012
Mammillaria ignota (Mammillaria albilanata subs. oaxacana) Photo by: Valentino Vallicelli
Mammillaria ignota (Mammillaria albilanata subs. oaxacana) Photo by: Valentino Vallicelli
Mammillaria ignota (Mammillaria albilanata subs. oaxacana) Photo by: Cactus Art
Mammillaria ignota (Mammillaria albilanata subs. oaxacana) Photo by: Cactus ArtCultivation and Propagation: Water regularly in summer, but do not over-water (Rot prone). Use a pot with good drainage and a very porous potting media. Keep dry in winter. Feed with a high potassium fertilizer in summer. It is quite frost resistant if kept dry, hardy as low as -5° C (some reports give it hardy to -12°C). Outside full sun or afternoon shade, inside it needs bright light, and some direct sun.
Propagation: Sow directly after last frost.