premise: Gymnocalycium fischeri is a globular cactus belonging to the family Cactaceae. The first description was in 2002 by Josef Halda Jacob, Petr Kupčák, Emil Lukasik and Jaromír Sladkovský. The specific epithet honors the Czech cactus collector Ladislav Fischer.
hypothesis: Ladislav Fischer gave Gymnocalycium fischeri its name
reason: It was named after him, but he did not give it its name