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Obregonia denegrii Fric 1925 The Czech botanist Alberto Fric, his discoverer, was exiled in Mexico from 1920. The name is in honor of president of Mexico Alvaro Obregón and its secretary of Agriculture, Mr. Denegri.
It was described as a simple plants globular-squashed. They grow leveled with the ground, with the sunk and woolly apex, of grayish green color or green chestnut tree, of up to 15 cm of diameter. Great, napiforme root. Without ribs. Tubercles ready in spiral, lengths, triangular. Small areolas, in the apex of tubercles, with wool when young. Of 3 to 4 spines in the young tubercles, that will fall more ahead, of 5 to 15 mm in brown length, turgid or slightly curved, flexible, whitish with dyes. It blooms during the day in summer; the flowers grow between the wool of the apex, in center of the stem, with form of funnel, white with grayish in the external segments of perianthus of 20 to 25 mm in length and of 10 to 15 mm of diameter, with naked pericarpel; the filaments are reddish purple, the anthers yellow, the style is white and the greenish lobes of stigma white. The fruits are naked and fleshy, in form of nail, white color, dry when mature. Pear-shaped seeds, with the black head, of 1 to 1.4 mm in length.
you can only fins this plant in the valley of Jaumave, near City Victory, in the state of Tamaulipas, the northeast of Mexico. There it grows in the inferior part of a dense forest, on the leaf and in the shade. It has been collected abundantly, reason why there are including the sort in Appendix I of CITES, the highest protection. In its only well-known habitat it grows abundantly. It undergoes danger by the use like pasture of the land where it grows. The status of Obregonia like sort differentiated from a single species, seems enough accepted at the moment, although Berger related it to Strombocactus and Marshall with Ariocarpus. It looks like this last one, but it carries spines. In the studies of DNA sequences made in 2002 by Butterworth, Cota and Wallace its affinity with the Lophophora williamsii is appraised. Obregonia denegrii is cultivated from seeds, growing slowly, but conserving its beautiful proportionate form. The graft is not advised. It requires a rigorous winter rest, without water. In summer it needs much heat and the watering can be abundant but be sure that the substratum is well dry between irrigation and irrigation. The substratum has to be well drained to avoid the rot of its root. |
