Mucoromycotina

Mucoromycotina is a subphylum of fungi within the phylum Mucoromycota. It comprises a diverse group of mostly saprotrophic organisms that occur in soil, decaying vegetation, dung, and stored foods. The subphylum includes the familiar bread molds of the order Mucorales—genera such as Mucor, Rhizopus, Lichtheimia, Rhizomucor, and Cunninghamella—as well as other lineages including Endogonales.

Most Mucoromycotina form coenocytic (aseptate) hyphae that grow rapidly. They reproduce asexually by sporangia bearing sporangiospores on specialized sporangiophores. Sexual reproduction involves the fusion of compatible hyphae to form zygosporangia, within which zygospores develop. The life cycle features both abundant asexual propagation and a sexual stage that produces resilient resting spores.

Ecology and associations are diverse. Many species are environmental decomposers in soil and on decaying matter, contributing to nutrient cycling. Some lineages, notably Endogonales, form mycorrhizal associations with plants, including early-diverging land plants, providing a link to arbuscular-type symbioses. Others are plant pathogens that cause rots or damping-off diseases. Several species are opportunistic pathogens of humans and animals, capable of causing mucormycosis in immunocompromised individuals.

Economic and practical importance varies. Some Mucoromycotina spoil stored foods and are encountered as bread molds; others have roles in fermentation or enzyme production, and a subset is studied as model organisms in fungal biology.

Taxonomy has shifted in modern fungal systematics. Zygomycota, a historically used group, has been reorganized, with Mucoromycotina recognized as a subphylum within Mucoromycota rather than a subdivision of a broader Zygomycota, reflecting revised understanding of fungal relationships.