Microfungi comprise a loosely defined artificial group of Fungi and fungal-like organisms that include such things as bread molds, plant pathogens, powdery mildews, rusts, slime molds, and water molds. In general, these fungi are difficult or impossible to see with the unaided eye.  A taxonomical classification of microfungi suggests the group contains 4468 genera and 55,989 species.

Microfungi are ubiquitous throughout the world and some cause major economic impacts as pathogens of animals, plants, and other fungi. Many microfungi are harmless saprobes, breaking down large complex chemical structures such as lignin found in wood into usable simple compounds. Despite their importance, little is known about the diversity, distribution, ecology, or host relationships of microfungi throughout the United States.

The Microfungi Collections Consortium (MiCC) is a collaborative effort among 38 US institutions to digitize specimen label data from 2.3 million North American microfungi specimens and make these data available online to the broader community through the MyCoPortal website.  A proposal submitted in October 2014 to the National Science Foundation's Advancing Digitization of Biodiversity Collections program was granted in July 2015.  Dr. Andrew N. Miller of the Illinois Natural History Survey serves as the Project Leader.