There is still no agreement with the naming. He is currently known under various names, in the "Tropical Pacific Invertebrates" by Patrick L. Colin and Charles Arneson, he is listed as Gomophia gomophia and illustrated on page 245.
Also in Neville Coleman's "Sea Stars - Echinoderm Discoveries" he is listed and illustrated there by the name "Coleman's nippled Sea Star".
He will use both algae and sponges as food as well as Detrius. I saw one "eat" a sponge, but maybe he has only eaten the algae which were on the sponge, who knows?