Harmothoe (Fifteen Scaled Worms) is a genus of segmented worms in the family polynoid scaleworms. They are biodiffusors. Individuals can grow to 100 mm. They are crawlers.
Definition: directly or indirectly modulating the availability of resources to other species, by causing physical state changes in biotic or abiotic materials; modifying, maintaining and/or creating habitats
Definition: A group of species that exploit the same food resources, and/or use the same feeding or foraging methods. http://en.wikipedia.org/wiki/Guild_(ecology)