This plant is an extreme form of G. spegazzinii.It  is an "European" variety selected originally from  plants with  open cluster of long and strong spines. This plants was at first multiplied asexually or by controlled pollination.

Family: Cactaceae (Cactus Family)

Gymnocalycium spegazzinii var. major Backbg. nomen nudum

Scientific name:   Gymnocalycium spegazzinii Britton & Rose
Pubblished in: The Cactaceae; descriptions and illustrations of plants of the cactus family 3: 155, 1922

Origin:  Garden origin (Nursery selected form)

Conservation status: Listed in CITES appendix 2.

Gymnocalycium spegazzinii var major.
It  is an "European" variety selected originally from  plants with  open cluster of long and strong spines.

Description: This plant is an extreme form of this very variable rich in forms species, but it is not justified the attribution of the rank of variety.
The plants that are today in cultivation with the name “Major” are plants with high homozygosis levels derived from the first selected specimens originally used to describe the new form. This plants was at first multiplied asexually or by controlled pollination, so they remained - generations by generation - almost unchanged in appearance. So the initial extreme types with the long strongly open cluster of spines involuntary began in the course of time to be cultivated and is now in our collections as good form. A whole series of such "European” form and variety of cacti is now recognized, however in nature plants shows - in the same place too - all their intermediate forms and passages and grow one to each other.

Cultivation: Keep this plant almost dry in winter at a minimum temperature of 0°C, prefer a low pH  compost otherwise growth will stop altogether. The plant tolerate extremely bright situations  but enjoy  some shade during the hottest part of the day in summer.

Propagation: Seeds (seldom produces offsets)