Wiktionary
saprophagy
n. The eating of non-living organic material.
Wikipedia
Saprophagy
Saprophages, are olophages that obtain nutrients by consuming decomposing dead plant or animal biomass. They are be distinguished from detrivores in that saprophages are sessile consumers while detrivore are mobile. Typical saprophagic animals include sedentary polychaetes such as amphitrites (Amphitritinae, worms of the family Terebellidae) and other terebellids.
The eating of wood, whether live or dead, is known as xylophagy. Τhe activity of animals feeding only on dead wood is called sapro-xylophagy and those animals, sapro-xylophagous.