Mucor is a genus of approximately 40 species of molds in the family Mucoraceae. They are commonly found in soil, digestive systems, plant surfaces, some cheeses like Tomme de Savoie, rotten vegetable matter, and iron oxide residue. Mucor spores or sporangiospores can be simple or branched and form apical, globular sporangia that are supported and elevated by a column-shaped columella. Mucor species can be differentiated from molds of the genera Absidia, Rhizomucor, and Rhizopus by the shape and insertion of the columella, and the lack of stolons and rhizoids. Some Mucor species produce chlamydospores. They form mold with irregular non-septate hyphae branching at wide angles (>90°) .

Mucor fungi cause the group of infections referred to as zygomycosis (mucormycosis) . Mucor is a filamentous fungus found in soil, plants, and decaying matter. Mucormycosis is a rare but serious fungal infection caused by a group of molds called mucormycetes. These molds live throughout the environment and mainly affect people who have health problems or take medicines that lower the body’s ability to fight germs and sickness. It most commonly affects the sinuses or the lungs after inhaling fungal spores from the air. It can also occur on the skin after a cut, burn, or other type of skin injury.

Most species of Mucor are unable to infect humans and endothermic animals due to their inability to grow in warm environments close to 37 degrees. Thermotolerant species such as Mucor indicus sometimes cause opportunistic, and often rapidly spreading, necrotizing infections known as Zygomycosis. Mucor infections occur in most cases through the inhalation of spores, ingestion through surgical and accidental wounds, ears, nose, nails, and eyes. Most human infections are caused by M. circinelloides and similar species such as M. indicus, M. ramosissimus, M. irregularis, and M. amphibiorum. However, M. hiemalis and M. racemosus have also been reported as infectious agents.