The Wrinkled Star Pteraster militaris

We have found only one species which is likely to be a predator. This is Wrinkled Star, Pteraster militaris. It is occasionally observed with the stomach everted over a living Cloud Sponge which is highly suggestive of feeding.  It is also reported to feed on another species of sponge and on certain hydrocorals.

Henricia sanguinolenta

The white thin armed sea star Henricia sanguinolenta. Is occasionally seen on living Cloud Sponges but it is unclear whether or not it is feeding on sponge tissue.

Desmacella cf. vestibularis in a Cloud Sponge

Several kinds of sponges take up residence within the skeletal framework of dead Cloud Sponges. At least one of these, Desmacella cf. vestibularis, extends in dead skeleton to the edge of living tissue.

It is possible that it kills the sponge, not for food but for habitat.