Xerophyte

Central Spines

6-12, rigid, straight or slightly curved, widely spreading or nearly erect, 8-55 mm long, less than 1 mm diameter at base, reddish brown to nearly black, base yellow or cream. On some plants, the spines can also be grey or golden.

Seeds

Grey to black, 2-3 long 1.5-2 mm thick, papillate but not rugose.

Description

Pediocactus nigrispinusSN|19699]]SN|19717]] is a rounded cactus that may be solitary or clump-forming, occasionally with over 50 heads, and forming large mounds to 30 cm or higher, and 60 cm across. The spines usually are reddish brown to nearly black, but variable in thickness, yet in their colour. The flowers are showy usually pink, but ranging from purple to white. Occasionally peach coloured or yellow flowers can be found as well. No known morphologic character supports the taxonomic recognition of infraspecific taxa within Pediocactus nigrispinusSN|14637]]SN|19717]]. Characteristics used to distinguish the three described subspecies almost completely overlap.

Note

In botanical Latin an adjective derived from 'niger' that means black, and 'spina' a spine, with black spines.

Flowers

Showy - often 4-8 buds at the top of each stem – funnel-shaped, each at the tip of a tubercle, 1-3.5 long, 2.5-5 cm broad, red-violet to yellowish-green. Perianth segments and stamens numerous, all joined at the base. The scales on the tube and outer perianth segments of flower tube minutely toothed, laciniate, or entire and undulate. Outer perianth segments with greenish brown midstripes, oblong-cuneate, 12-25 mm long, 4.5-9 mm broad. Inner perianth segments white, pink, magenta, peach, yellow or yellow-green, 19-27 long, 5-10 mm broad. Ovary inferior, 1-celled.

Blooming Season

The flowers open during the day, bloom in late spring to summer (May-July) and seeds are ripe one month later, though this can vary substantially depending on the weather.

Spines

Smooth, hard, and rigid, distinguishable as radial and central.

Stem

Globose and depressed to elongate-ovoid, single or in clumps, 5-30 tall, 5-15 cm thick, covered with tubercles 12-25 mm long, in 8-13 spiral rows.

Radial Spines

10-30 per areole, smaller, spreading at right angles to tubercles nearly straight, white to dull reddish brown, 8-20 mm long.

Fruits

Fruit subglobose to short cylindric, 6-11 mm, 5-10 mm in diameter, green tinged with red, drying reddish brown.

Areoles

Oval, hairy.