General: Desert Spinystar (Escobaria vivipara var. deserti) is a small, round cactus that grows to about 6 inches tall by 3-inches wide (usually 3 by 2 or smaller). The stem does not have the ribs (flutes) seen in some other cactus. The stem is densely covered with relatively long, stout, straight white spines with reddish-brown tips (none are fish-hook shaped), and all of the spines are pressed closely against the stem. Desert Spinystars tend to grow in small groups, so if you find one, look around for more.

Desert Spinystars are small and inconspicuous, but interesting members of desert vegetation communities. Desert Spinystars occur in the Upper Sonoran (Mojave Desert Scrub) life zone.

This species is difficult to find because they are small and occur infrequently, but look for them on rocky limestone outcrops and along limestone ridges. A "dense" population can be found just northeast of the Red Rock Canyon NCA Visitor Center. A few can be found along the trail up Fossil Ridge.

Family: Cactus (Cactaceae).

Other names: Mammillaria cactus, Coryphantha deserti var. deserti.

Plant Form: Short, usually solitary, rounded stem that emerges from the ground. Unbranched.

Height: Usually 2 to 3-inches tall (to 6-inches tall and 3-inches in diameter).

Leaves: None (reduced to spines).

Flowers: Blooms in early summer. Inflorescence: solitary flowers at the top of the stem. Flowers straw to yellowish, about 1-inch in diameter. Flowers open during the afternoon and only stay open for two hours or so.

Seeds: Small (2 mm), brown.

Habitat: Limestone soils and rocky limestone ridges.

Distribution: Southeastern California, southern Nevada, Southwest Utah, northwest Arizona.

Elevation: 3,300 to 8,000 ft.

Comments: