Xerophyte

Seeds

Sub-cylindrical, rounded, sometimes enlarged at base.

Note

tortuosus,-a,-um; from Latin. tortuosus (from torus, bend, curve), for the spines that are bent or twisted in different directions.

Flowers

Several produced together at apex, yellow, about 2.5-5 cm in diameter. Tube short filled with wool, bristly brown hairs and green scales becoming gradually longer above. Outer segments oblong shortly pointed. Inner perianth-segments in two whorls, mucronate and fringed at apex. Stigma yellow or pale red.

Spines

4-16 mm long straight or somewhat curved and twisted, pale yellowish to reddish. Radial spines in 4-6(-7) pairs, the upper ones slightly shorter, the other all equally long. Central spines 4 to 6, brown, slightly larger and spreading, the upper one shorter.

Ribs

10-15, occasionally more, sub-vertical, arched, rounded-triangular in cross section, sides surfaces convex, forming deep angled sinuses and rounded apically

Stem

Hemispherical to depressed, dark green, 13-18 cm in diameter, apex woolly and somewhat depressed.

Fruits

Protruding, sub-globose, scales thin, with short wool and longer bristles.

Areoles

Shallowly notches between tubercles, closely set. Juvenile ones woolly.