organism that obtains nutrients by consuming detritus

A detritivore (also known as decomposers) is an animal that feeds on dead organisms (living things) and breaks them down into smaller molecules. Detritivores are essential in the ecosystem as they return important materials such as carbon (see carbon cycle) back into the environment. Examples of common detritivores include earthworms and woodlice, but also includes microscopic (things that can only be seen using a microscope) bacteria.

Bacteria (Escherichia coli cells magnified 25,000 times)