Xerophyte

Central Spines

3-7 central spines, up to 12 mm long, brown to brownish black.

Seeds

Oblong-globose 1.2 to 1.3 mm long and 1.1 to 1.2 mm wide, dark brown.

Roots

Main root thin (up to 7 cm long) highly branched, but in larger plants the main root is barely recognizable.

Flowers

Buds brownish, mostly born in the old areoles on the side of the stems, rarely on older areoles near the base of the plant. Flowers yellow with white throat, 2.5 to 3.5 cm across, scentless, sometimes with fruity, mouldy or musty odours, also smelling like lemon balm (Melissa) or jasmine. Outer tepals scaly, yellow with darker brownish red tips, inner tepals yellow with a clear white-yellow base. Carpel and tube with greenish or reddish yellow, apiculate scales. Stamens yellow or yellowish. Pistil white to yellowish with 5-6 papillose, whitish or yellowish stigma-lobes.

Spines

Not easily distinguishable as radial and central.

Ribs

about 32, with conical tubercles in spirals.

Stem

Solitary, flattened-spherical, with concave apex, dark green to dull olive-green, up to 10 cm tall and 7 cm in diameter.

Radial Spines

about 24 soft, bristle-like, from white to brown and black, up to 10 mm long.

Fruits

Olive-green or brownish, up to 5 mm in diameter, with scale scales of the same colour. Lower scales with or without few white hairs.

Areoles

Rounded to oval 3 to 4 mm long, 2 to 3mm wide.