Stapelia with Scale Infestation
I bought two plants but am not sure what they are . one look like it was sufering from rot so I removed the bad sections and repotted in new cactus type mix. Wound up with two pots from one because root system was large. Some of the plant is whiteish, Is this sunburn?
The one that is whitish is a Stapelia, the other is a Huernia, both closely related.
The Stapelia has an infestation of Scale, which is an insect that is feeding on your plant. As bad as it looks I would recommend removing all the white stems and taking cuttings from the green stems to replant them, letting the cut ends heal for about a week before planting them in new fresh dry cactus soil. I would spray the green stems you are keeping with a strong insecticide that can handle Scale. We sell a product called Don’t Bug Me. You will need to start over again with new fresh soil. Spray in the evening and out of direct sun to prevent sunburn.
You also might want to spray any plants that are near this one as a preventative measure.
The Huernia looks fine to me in the photo.