Gymnocactus species nova

Gymnocactus species L1159 blooming in Hamilton, October 16th.

This plant arrived here from nurseries in California labelled as L1159 Gymnocactus species nova. In fact when I compare it to the literature I'm not sure why it's considered a species nova because it looks like Gymnocactus viereckii to me. It was blooming in Hamilton, Ontario Sunday October 16th.