I wanted to solve your mystery about Gymnocalycium damsii ~versus~ Gymnocalycium anisitsii. So, I went to several websites and it appears that the former is a taxonomical synomym for the latter. Scientific names can change over time as more information is learned. The following except from Wikipedia gives an example of how scientific classification can change over time. The source article gives more detail, for anyone interested! 🙂
In scientific nomenclature, a synonym is a scientific name that applies to a taxon that (now) goes by a different scientific name... For example, Linnaeus was the first to give a scientific name (under the currently used system of scientific nomenclature) to the Norway spruce, which he called Pinus abies. This name is no longer in use: it is now a synonym of the current scientific name, Picea abies. [source]
And what a beautiful little flower it is, regardless of the scientific name! Great shot, and such a pretty thing! 😊
That explains it. No wonder people get confused :p They keep changing the names, moving to different groups or creating new ones. It is the same with orchids.
Thank you for the research :)