Rapicactus beguinii (N.P.Taylor) Lüthy

국표에는 없다.

Origin and Habitat: Northeast Mexico to central Mexico, Zacatecas, San Luis Potosí, Coahuila to Hidalgo.
Habitat: It grows in scattered colonies, on different mountains, on warm steppes, and in pine forests or bushes, at altitudes of around 1900-2100 m., on lime with a high content of organic parts and a slightly basic pH. Localities are difficult to reach, and the main danger comes from fires.

Description: Body usually solitary, globose. Hardly offsetting in cultivation.
Stem: Spherical or somewhat conical, rounded above; apex rather deeply sunken, but fully hidden by the snow-white, dense wool; blue-green, 6-8 (10) cm high and 6-8 cm in diameter. Ribs fully arranged in tubercles, from 13 to 21, rather dense spirals, rhombic or sub-quadrangular, conical; the top somewhat compressed from the sides, with sharp upper and lower edges. The seedlings tend to become quite cylindrical.
Roots: Carrot-shaped
Flower: Flower broadly funnel-shaped. Tepals linear, blunt, green with violet edge; inner linear - lanceolate, pointed, magenta with lighter edges of petals. Length and diameter of the flower 2-2.5 cm. White Filaments; the Anthers are dark chrome yellow. The white style towers over them with 6 recurved lobes.
Phenology: Blossoming time: summer
Fruit: Fruits, urn-shaped, are 12 mm long.
Spines (in adult plant): Close-packed, radial, mostly 12, awl-shaped, very sharp, sticking out up to 17 mm, snow-white, translucent, young almost glass-like, black tipped. Central spines 1, much longer (up to 30 mm), somewhat stronger, white, but at the top and further down, dark brown to black. Later they become grey, and the radial spines radiates horizontally, almost comb-like.
Juvenile spine: Plumose, soft, flexible, not pungent. During the first year near the base thin feathery hairs begin to form. Often the spine is densely covered, with hairs up to its tip. Spines of two-year-old seedlings (see figure) differ only in being longer and more ragged. There are no central spines; all are radial.

Rapicactus beguinii (llifle.com)

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