About Leuchtenbergia principis Fisch. ex Hook.
Leuchtenbergia principis is a very slow-growing plant that typically grows individually, and only rarely produces sprouts. It reaches a height of 20 to 35 cm (7.9 to 13.8 inches), and rarely grows as tall as 70 cm (28 inches). It has a cylindrical stem that becomes bare and corky at the base as it ages. The plant has large, fleshy roots, including a large, tuberous taproot. Its shoots range from spherical to slightly cylindrical. It has long, slender, grayish-green tubercles that measure 6–12 cm long, with purplish-red blotches at their tips. The tubercles are topped with papery spines, which gives the plant a similar appearance to an agave. Older basal tubercles dry up and fall off the plant. After approximately four years of growth, yellow, fragrant, funnel-shaped flowers 5–6 cm in diameter may grow at the tips of tubercles at the end of areoles near the plant body; these flowers open during the day. The pericarpel of the flowers has scales. The fruits are egg-shaped to oblong, and they become dry when ripe. They are smooth and green, measuring 3 cm long and 2 cm wide. The seeds are broadly oval, black to brown, 2.4 mm (0.094 inches) long and 2 mm (0.079 inches) in diameter. This species is distributed in the Mexican states of Coahuila, Guanajuato, Hidalgo, Nuevo León, San Luis Potosí, Tamaulipas, and Zacatecas, where it grows in Chihuahuan Desert vegetation on limestone soils.
