Rhizophlyctis rosea is a ubiquitous, aerobic, zoosporic fungus, typically growing in agricultural soils. An overview is here given on the effects of major abiotic and biotic environmental factors on the growth, development, distribution and survival of R. rosea, and on the diversity, stability and activity of plant cell wall-degrading enzymes produced by R. rosea. Its habitat is in organic debris, near the soil surface where light penetrates. R. rosea is a highly effective plant biomass degrader, producing a diverse array of secreted enzymes. R. rosea has multiple mechanisms for sensing daylight intensity, wavelength and duration. Putative genes, encoding four different types of light sensitive proteins (rhodopsin, white collar-1, vivid-like LOV and phytochrome proteins) were detected in the R. rosea genome, providing light sensing ability to R. rosea to allow this fungus to remain in euphotic environments, and/or to enable the naked zoospore to avoid the detrimental effects of UV light.