What Adaptation of sea worm?
An adaptation of a sea worm is that they can use their bodies as protection from predators. Some types have a coating they can release, or stinging appendages.
A starfish and a scale worm have a commensal relationship (commensal is a type of symbiotic relationship where the host benefits the stowaway but doesn't harm the host): The sea star provides protection and food for the scale worm. The scale worm doesn't harm the sea star, therefore it is a commensal relationship.
There are far too many invertebrate species to list. Note that there are far more invertebrate species than vertebrate species. However, I here are a list of invertebrate phyla: Acanthocephala (a phylum of worm) Acoelomorpha (a phylum of worm) Annelida (a phylum of worm) Arthropoda (spiders, crabs, etc) Brachiopoda Bryozoa Chaetognatha (a phylum of worm) Cnidaria (corals, sea anemones, jellyfish, etc) Ctenophora (comb jellies) Cycliophora Echinodermata (sea urchins, starfish, etc) Echiura (a phylum of worm)…