Detritivores (also known as detrivores, detritophages, detritus feeders or detritus eaters) are heterotrophs that obtain nutrients by consuming detritus (decomposing plant and animal parts as well as feces).[1] There are many kinds of invertebrates, vertebrates, and plants that carry out coprophagy. By doing so, all these detritivores contribute to decomposition and the nutrient cycles. Detritivores should be distinguished from other decomposers, such as many species of bacteria, fungi and protists, which are unable to ingest discrete lumps of matter. Instead, these other decomposers live by absorbing and metabolizing on a molecular scale (saprotrophic nutrition). The terms detritivore and decomposer are often used interchangeably, but they describe different organisms. Detritivores are usually arthropods and help in the process of remineralization. Detritivores perform the first stage of remineralization, by fragmenting the dead plant matter, allowing decomposers to perform the second stage of remineralization.[2]
Plant tissues are made up of resilient molecules (e.g. cellulose, lignin, xylan) that decay at a much lower rate than other organic molecules. The activity of detritivores is the reason why we do not see an accumulation of plant litter in nature.[2][3]
Detritivores are an important aspect of many ecosystems. They can live on any type of soil with an organic component, including marine ecosystems, where they are termed interchangeably with bottom feeders.
Typical detritivorous animals include millipedes, springtails, woodlice, dung flies, slugs, many terrestrial worms, sea stars, sea cucumbers, fiddler crabs, and some sedentary marine Polychaetes such as worms of the family Terebellidae.
Detritivores can be classified into more specific groups based on their size and biomes. Macrodetritivores are larger organisms such as millipedes, springtails, and woodlouse, while microdetritivores are smaller organisms such as bacteria.[4][5]
Scavengers are not typically thought to be detritivores, as they generally eat large quantities of organic matter, but both detritivores and scavengers are the same type of cases of consumer-resource systems.[6] The consumption of wood, whether alive or dead, is known as xylophagy. The activity of animals feeding only on dead wood is called sapro-xylophagy and those animals, sapro-xylophagous.