Echinocereus parkeri

Echinocereus parkeri is a small cactus from northeastern Mexico. It belongs to the cactus family, Cactaceae. Its range includes Coahuila, Nuevo León, Tamaulipas, San Luis Potosí, and Zacatecas. It grows in the southern part of the Chihuahuan Desert. There, it is widespread and common in suitable sites. Its wild home is desert or dry shrubland. Plants grow mainly on the tops of limestone hills. The species account places these sites at 4,760–6,230 feet [1,450–1,900 metres] above sea level.

This succulent subshrub makes low clumps with many stems. Some plants form tight mounds, while others have more open growth. The stems can be cylindrical or narrow toward their tips. They reach about 0.49 feet [0.15 metres] in height. Each stem measures about 0.07–0.20 feet [0.02–0.06 metres] across. These measurements describe the stems, not the whole clump. Each stem has six to ten ribs with pronounced bumps. The low form, ribbed stems, and long spines define its appearance.

The spines differ in size, number, and colour. Each group has one to eight central spines. These start dark, then turn glassy white or yellowish. They measure about 0.07–0.21 feet [0.02–0.065 metres] long. Six to eighteen slender radial spines surround the central ones. These are usually glassy white. They measure about 0.02–0.04 feet [0.007–0.012 metres] long. The straight central spines can stand well beyond the stem surface.

Flowers grow near the stem tips and open by day. Their funnel-shaped blooms range from magenta to deep pink. White throats mark the centre of each flower. Blooms measure about 0.15–0.18 feet [0.045–0.055 metres] long. Their width reaches about 0.15–0.20 feet [0.045–0.06 metres]. The fruit is green and almost round, with white flesh. Glassy white spines cover the fruit but tend to fall away. The supplied species account gives no flowering months.

LLIFLE describes this cactus as easy to grow and willing to flower. It also notes that the species is scarce in collections. Its compact clumps and bright flowers give it ornamental interest. The species-level evidence does not set out detailed growing conditions. It gives no firm frost limit or watering schedule. Nor does it establish edible uses, toxicity, or specific pest problems.