Ascomycetes are commonly known as sac-fungi. These are either unicellular e.g., yeast (Saccharomyces) or multicellular e.g., Penicillium. They are saprophytic, decomposing, parasitic or coprophilous (growing on dung) in nature.

Zygomycetes are found in aquatic habitats and on decaying wood in moist and damp places or as obligate parasites on plants. The mycelium is aseptate and coenocytic. Squirting fungus-Pilobolus crystallinus is a coprophilous or dung mould.