The species was described by J. Halda, P. Kup?ak, E. Lukašik and J. Sladkovský in 2002. By then, the plants could be found in European collections for quite some time. R. Kiesling identified them as G. stuckertii.
Gymnocalycium fischeri can be found in the area of the western to south-eastern extension of the Sierra de San Luis and as far as the region around San Francisco del Monte de Oro.
The plants grow separately and reach a height of up to 100 mm. Flowers appear near the vertex and can be markedly large - I found plants with flowers that were up to 110 mm long. Their colour spectrum reaches from ivory white to light pink, usually with a darker pink gullet.
The climate in the province of San Luis is hot and dry during summer. The ridges of the extension of the Sierra San Luis are overgrown by low shrubs and grass. Gymnocalycium fischeri grows sheltered by shrubs and tall grass, where humus can accumulate.