About Coryphantha cornifera (DC.) Lem.
Coryphantha cornifera (DC.) Lem. most often grows alone, though this is not always the case. Its stems range in shape from globose to cylindrical, and are generally a dull olive-green color. This cactus grows 6 to 12 cm (2 to 5 in) tall, with a diameter of 8 to 15 cm (3 to 6 in), and has either fibrous or semi-fibrous roots. On older plants at least, the top of the cactus is blunt and depressed, and may be covered in white wool. The cactus surface is split into numerous tubercles that resemble the base of a green chili pepper. Spines grow from specialized structures called areoles, which sit at the top of each tubercle. This species typically produces 12–18 radiating spines per areole, and often also has 1–4 longer, sturdier central spines; spine arrangement is highly variable across individuals. Coryphantha cornifera grows in semi-arid scrub and grasslands, and is occasionally found in disturbed areas within oak forests. It prefers limestone substrates on flat or gently sloping land, and occurs at elevations between 1,400 and 2,200 meters (4600–7200 feet). It flowers from June to July, and its flowering period sometimes extends into September. This species is endemic only to the highlands of central Mexico. Research-grade observations of Coryphantha cornifera documented on the iNaturalist website come from the Mexican states of Zacatecas, San Luis Potosí, Jalisco, Guanajuato, Querétaro, and Hidalgo.
