Xerophyte

Central Spines

Usually one (but up to 4) the dominant straight (sometime bent toward the apex), subulate (1,5)2,5-3,5(-5) cm long, the other straight upwards, slightly spreading outwards, slightly darker than radials.

Seeds

Brown, nearly smooth, about 2-3 mm long, somewhat flattened and kidney-shaped, with a lateral hilum.

Description

Coryphantha robustispina subs. scheeriSN|10068]]SN|10314]] is a low-growing solitary (occasionally multi-stemmed) cactus related to Coryphantha sulcataSN|10314]]SN|10068]].

Axils

At first with white wool, then naked and broadened.

Tubercles

in 5-8 series, 7-12(-30) mm long, 15-19 mm wide, conical to cylindrical, prisma shaped at the base, fairly firm, prominently grooved and thick with 1 to 4 reddish-brown nectar glands. Furrow deep and woolly.

Flowers

Funnel-shaped, silky, dark golden-yellow to greenish-yellow, rarely streaked or blushed with reddish in centre, 4-6.5 cm long, 5-7 cm in diameter, yellow stamens yellow to orange.

Blooming Season

April-July, and possibly to as late as November.

Stem

Hemispherical to egg shaped or somewhat conical, dull green, strongly tuberculate, 5-15 cm tall, 5-10(-15) cm in diameter or exceptionally taller especially in cultivation. Apex rounded wooly.

Radial Spines

(6-)8-13(-16) straight stiff, needle-like, yellowish to creamy-white with darker tips. Lower one often brownish (1-)2-2,5(-3.5) cm long, some upper radials often thinner, much like the central spine and closer set, the other horizontal spreading and radially arranged.

Fruits

Green, ovoid to club-shaped, 3.5 to 5.5 cm long , 1.2 to 2 cm in diameter, the pulp juicy, sweet and mucilaginous, flowers remnant deciduous when mature.

Areoles

Woolly when young, oval approx 3-4 mm wide, 5 mm long.