Wolfie, this is what I think is a carpet anemone that looked yellow...
(I see the colors are still a bit off. It's a dark green background and those rows are brown. I guess now that I got up and looked at them again, maybe the tips of what looks like polyps are yellow. They used to be brown. Everything is changing...)
This is the thing that smacks of a leather, but it's an SPS. You should be able to see the polyps. The inside is hard blue/white coral. Any clue what it is?