Each ascoma contains a single ascus containing eight ascospores. "Z. bailii" produces sexual spores (ascospores) in a sac called ascus (plural&colon; asci). The asci are cylindrical with a thickened ascus tip. The eight ascospores are produced inside an ascus. Each ascus contains one to four ascospores. Typically, a single ascus will contain eight ascospores. Each ascus contains 1-4 ascospores. Then the ascospores are released from ascus. An ascus (plural "asci") is then formed, in which karyogamy (nuclear fusion) occurs. The zygote grows into the ascus, an elongated tube-shaped or cylinder-shaped capsule. When each ascus becomes engorged with fluid it extends outside the perithecium and releases spores. One further mitotic division leads to four A and four nuclei in each ascus. As a result, the ascus will contain four pairs of spores. The spores, which number two (more rarely three) per ascus are characteristic for this species. One further mitotic division leads to four "A" and four "a" nucleus in each ascus.