Ascospores are a type of reproductive spore produced by fungi in the phylum Ascomycota. They are formed within a specialized sac called an ascus, which typically contains eight ascospores. This process is part of the sexual reproduction cycle of these fungi, allowing for genetic diversity. Ascospores are often released into the environment when the ascus ruptures, enabling them to disperse and germinate under suitable conditions. They play a crucial role in the life cycle of many fungi, contributing to their survival and propagation in various ecosystems.