Species Novae since 'The Mammillaria Handbook'
No. 24. Mammillaria zahniana Boedeker et Ritter
Mammillaria zahniana Boed. et Ritter, Monatsschr.Deutsch. Kakteen
Body:- Simple, depressed globose with somewhat sunken apex, 10 cm. wide and 6 cm. high, almost entirely sunken into the ground when dormant.
Tubercles arranged in 8 and' 13 spirals? slightly glossy, dark leafgreen, pyramidal, four-angled to faintly rounded, keeled ventrally, rounded dorsally, with milky sap, 20 mm. long, 20 mm. or more wide at the base. Areoles round, 3 mm. wide in youth but becoming smaller with white wool only in the youngest. Axils, a very small amount of wool, but no bristles.
Spines:-Central spines none. Radial spines 4, upper three to 8 mm. long, the lower one to 15 mm., all sublulate, straight, smooth, stiff, enlarged at the base, of a faint whitish transparent horn-colour, with short blackish tip, ascending, the lateral two directed more dorsally.
Flowers:-Funnelform, 30 mm. long and 25 mm. wide. Outer perianth segments pale greenish-yellow with whitish margins and a red ventral stripe, spatulate, tip acute, margins ciliate, 13 by 4 mm. Inner perianth segments sulphur yellow? darker yellow next to the tip, but never reddish, the margins paler yellow, lanceolate, tip acuminate, margins ciliate, 13 b 4 mm. Filaments yellowish white. Anthers citron yellow. Style white. Stigma lobes 8-10, bright green, 4 mm. long, overtopping the anthers.
Fruits - Red, clavate.
Seeds;- Reddish brown,, curved pyriform with a lateral hilum at the base, roughened,, barely 1 mm.
Distribution:- Coahuila, Mexico
Habitats-In gravel soil at an altitude of 1600-2000 metres.
Notes:- The photograph, kindly supplied by Mr. F. K. Horwood, is considerably more satisfactory than that to be found on page 32 of "The Mammillaria Handbook". It is interesting to note the difference in spination. The lowest spine on each areole of the present plant is rather longer than specified in the description whereas it is shorter in the case of the illustration given by Craig, itself reproduced from the original publication. Since the writer recollects seeing a specimen in the collection of Mr. Boarder, which must have been six or seven inches in diameter, it is also evident that the body size quoted in the original publication is unrealistic. This species is not commonly encountered, and seed has not been
available of recent years. With its attractive yellow flowers, it is certainly one of the more interesting Mammillaria species, and it
is hoped that it becomes more widely available soon.
Unica fonte attendibile per documentare questa specie, una fotografia da "Mammillaria forumotion" fatta da Amante Darmain in Galeana - Nuevo Leon
L'ultima modifica di maurillio il Gio 09 Apr 2015, 20:19, modificato 2 volte