Not your "average" Schlumberger: https://houseplantspro.com/yellow-christmas-cactus/#:~:text=Yellow%20Christmas%20Cactus%20or%20Yellow%20Decembrists%20are%20plants,their%20width%20varies%20from%205%20to%208%20cm.

"The yellow color of the petals is not typical for the Decembrist in natural conditions. In tropical forests, only pink, red, orange, and white flowers can be found.

"The first grade of the Decembrist with yellow flowers was “Gold Charm” . It was bred by the American breeder R.L. Kobia in the 80s of the 20th century. The process of breeding the variety dragged on for 15 years. In the beginning, 50,000 plant seeds were selected from varieties with orange flowers, in which the yellow component prevailed over red and pink.

After their sowing, only 1 bush with yellow buds was grown, and even that one was too weak for a full-fledged “offspring”. It was crossed with a sturdy and vigorous white Schlumberger bush, resulting in about 200 seeds. Only 150 bushes emerged from the sown seeds, one of which became the “ancestor” of yellow-flowered zygocactus"

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I found the plant in the above photo about 7 years ago (2014) at Home Depot during a post-Thanksgiving "Black Friday" sale. I then bought a different one (paler yellow) the following year at the same place. I haven't seen another yellow "Christmas Cactus" since... The specific varieties were both unnamed when I bought my plants. But they are probably two of the named varieties in the linked article above.


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My photo was captured indoors under natural light.