Zygomycetes are one of the four major groups of fungi, the others being the Oomycetes, the Ascomycetes, and the Basidiomycetes. Zygomycetes are common, fast growing, and often overgrow and/or inhibit other fungi nearby. Rhizopus and Mucor are two of the most common Zygomycetes seen in the indoor environment. However, others are seen as well, including Syncephalastrum, Circinella, Mortierella, Mycotypha, Cunninghamella, and Choanephora. For further information, please see descriptions of these individual genera.