Ariocarpus disciformis subs. jarmilae (Halda) Halda

국표에 없다.

Origin and Habitat: Northern Mexico (Querétaro and Nuevo León)
Altitude: Around 1400-1500 metres above sea level.
Habitat: Strombocactus disciformisSN|2109]]SN|2103]] grows in central Mexico in shadow localities, often in crevices on vertical gypsum canyon-walls fulfilled with acidic soil. On the contrary the northernmost Strombocactus jarmilaeSN|2103]]SN|2109]] grows on limestone and likes more alkaline soils and full sun exposures.

Description: Strombocactus jarmilaeSN|12844]]SN|2109]] is a slow-growing, miniature taxa of doubtful validity, generally included in Strombocactus disciformisSN|2103]]SN|2103]]. It is appears to have a smaller body, with small flowers, long thin spines and some other minor differences. It blooms profusely, and starts flowering at an early stage of development when only 1 cm in diameter.
Habit: It is a geophytic plant, usually solitary, deep-seated, that flush with soil surface in habitat.
Stem: The body is flattened or spherical, not bigger than 4 cm in diameter (S. disciformis may reach 20 cm in age, and 3 to 9 cm across). The crown is slightly depressed and felted. The colour is blue-green with greyish tinge, the base covered with brown corky spots in age.
Tubercles: S. jarmilae has characteristic rhomboid tubercles other than those of S. disciformis and of Strombocactus pulcherrimusSN|2109]]SN|12844]]. They are firm, spirally arranged and imbricate, less than 1 cm tall. These tubercules are flattened and almost truncated above and somewhat horny or keeled below.
Spines: 4 to 5, erect, somewhat thinner, dark grey at the tips and pale grey at the base, up to 2 (or more) cm long, becoming calcified and in age falling at the stem base.
Roots: It has a thin central root and not the strong napiform root typical of S. disciformis.
Flower: Flowers of S. disciformis are larger and more fleshy, those of S. jarmilae are thin, smaller, and dehydrated soon. One to several arise on the crown, measure about 3 cm in length and breadth, are cream coloured.
Fruit: 7 mm across, splits down its length.
Seeds: Dust-like, very small, S. disciformis has nearly 2 times bigger seeds with pressed hilium, S. jarmilae has oval-shaped hilium.
Blossoming time: Flowers emerge early in spring and are freely produced throughout the summer, remaining open for 1-2 days.

Ariocarpus disciformis subs. jarmilae (llifle.com)