Honestly, I don't know the sea lilies or feather stars are a kind of sea creature. The information provided in wiki contains information which is hard to understand as well. If you are interested to know more, the link is here : https://en.wikipedia.org/wiki/Crinoid
So, I saw the word crinoid in your link and asked "Google" if Crinoids were living organisms. Here's the answer I got:
They may look like plants, but crinoids are actually animals. They have been around for about 450 million years. Though the ocean floor was once covered with "forests" of crinoids, most have become extinct. Modern-day crinoids now live only in very deep water.
I'm not sure how accurate some of that info is, but for the most part it answers your question as to whether it's a plant or not.
So, there you go, it's alive. It's always quite beautiful. I'd love to see a macro of those "arms". The color is also wonderful.
They may look like plants, but crinoids are actually animals. They have been around for about 450 million years. Though the ocean floor was once covered with "forests" of crinoids, most have become extinct. Modern-day crinoids now live only in very deep water.
I'm not sure how accurate some of that info is, but for the most part it answers your question as to whether it's a plant or not.
So, there you go, it's alive. It's always quite beautiful. I'd love to see a macro of those "arms". The color is also wonderful.