Body solitary, compressed spherical. Ribs 13-32, spirally arranged with large tubercles. Spines curved, central spines at least 1, radials to 15. Flowers white to pink inside, greenish outside.

Argentina

 

Other pale-flowered species (pink, orange, lilac) and without stripes on the perianth segments inlcude G. bueneckeri Swales from S Brazil which has 5-6 ribs and petals pink on both surfaces, and G. multiflorum (Hook.) Britton & Rose from N Argentina which has bell-shaped not funnel-shaped flowers.

Source: Thompson, A, ; Forbes, S.; Spencer, R. (1997). Cactaceae. In: Spencer, R.. Horticultural Flora of South-eastern Australia. Volume 2. Flowering plants. Dicotyledons. Part 1. The identification of garden and cultivated plants. University of New South Wales Press.