I cannot tell you the seed parent for Moon Maiden, however I have used 'Korspel Sport' a few years back to generate a series of plants with thicker leaves which is what I was after. One of the earlier ones was 'Emerald City'. Now I have several larger plants with the thickness but green. Moon Maiden was the first one with decent color. When it starts to grow in the spring it looks like it is going to be yellowish ivory but as time passes it gets darker and darker. It made me think of the light and dark sides of the moon. From there it was a leap to an old Duke Ellington tune- 'Moon Maiden'