Selosse et al. 2017, Ecology Letters, 20: 246–263.
Absorbotrophic (=osmotrophic) mixotrophy: uptake of soluble organic matter found in the environment, e.g., low molecular-weight molecules (Schmidt et al. 2013). The word ‘osmotrophic’ (‘osmomixotrophy’ in Schmidt et al. 2013) insidiously suggests that osmotic forces account for this process, while active uptake is involved, so that we prefer the term ‘absorbotrophic’. Low-molecular-weight molecules are targeted, but some enzymatic processing, outside of or inside the cell after endocytosis, can be involved. Absorbotrophy occurs in multicellular organisms, such as land plants and in virtually all algae. Because of this, some aquatic research scientists tend in practice to restrict the term mixotrophy to the combination of the next two strategies (Flynn et al. 2013), but we and others (e.g. Stoecker 1998) do not follow this restrictive definition. With the exception of a few microalgae, the physiological and ecological relevance of absorbotrophic mixotrophy remains poorly quantified.