Some recent finds in Morocco have yielded numerous examples of the Edrioasteroid Spinadiscus lefebvrei. It seems that they are all found "loose" in the rock. That is to say they are not attached to a shell or other obvious hard substrate. These come from the Tiouririne Formation (Ordovician, Hirnantian stage) near Alnif, Morocco. Here are a couple of examples that I recently added to my collection.
Ediroasteroids are echinoderms and their relation to starfish is fairly obvious. They were stationary suspension feeders that sifted the water for food particles.Compare these specimens with some from the Ordovician of Ohio that I blogged about Here.