Echinocereus adustus

Echinocereus adustus is a small cactus in the Cactaceae family. It comes from Chihuahua in northern Mexico. Records place it near Cusihuiriachic, Sahuirachic, and north of Chihuahua city. It grows in desert grassland and on hills with stones. These sites have loamy soil. Its native sites lie at 5,906–7,874 feet [1,800–2,400 metres] above sea level. Kew describes its broader habitat as desert or dry shrubland.

This succulent subshrub most often grows as a single stem. The green stem forms a short cylinder with fibrous roots. It can reach about 0.66 feet [0.20 metres] tall. Stem width is about 0.13 feet [0.04 metres], sometimes reaching 0.39 feet [0.12 metres]. These figures describe the plant, rather than a stated garden range. Each stem has 11–16 ribs. Small oval areoles sit close together along the ribs. They start with a woolly coat, which they later lose. The gaps between them measure about 0.013–0.023 feet [0.004–0.007 metres].

Each areole bears 5–18 radial spines in a comb-like pattern. These cream spines have darker tips and lie against the stem. They measure about 0.05–0.08 feet [0.016–0.023 metres] long. A plant may also bear one central spine per areole. This spine is stiff, straight, and dark brown to black. It can reach about 0.11 feet [0.035 metres] long. Some adult plants lack central spines altogether. Others develop them only after several years of growth. Young plants can flower before these central spines appear. Their presence or absence does not mark other differences in the described plants.

The flowers are magenta-pink, with a paler shade inside the throat. Their edges have a frilled look. Flowers measure about 0.15–0.20 feet [0.045–0.060 metres] long. Their width spans about 0.13–0.18 feet [0.040–0.055 metres]. The style is yellow, while its five or six stigma lobes are yellow-green. These flowers contrast with the green stem and pale radial spines.

The fruit has an oval shape and a brown-green skin. It takes about two months to ripen. At maturity, it dries and splits open. The seeds are black. The supplied species sources give no flowering months or garden hardiness range. They also provide no species-level guidance on watering, pests, or diseases. They do not establish edible uses or toxicity.