Me, suddenly: “How have I not written anything about decorator crabs???”
Also me: “Oh wait, it’s okay. I have.”
This is what happens when you’ve written more than 200 short stories and nearly a dozen novels. You have trouble remembering all of them at all times.
At least… it’s what happens to me. It’s possible that not everyone feels as strongly about the necessity of having written a piece of fiction involving decorator crabs as I apparently do.