English: On the left, an illustration of the current understanding of sexual reproduction in ascomycete fungi: haploid nuclei in the ascogonium move into an ascogenous cell, undergo nuclear fusion (karyogamy) to form one diploid nucleus, divide into four haploid nuclei by meiosis, and divide into eight haploid ascospores by mitosis. On the right, the now-rejected hypothesis of brachymeiosis: karyogamy occurs in the ascogonium and again in ascogenous cells, producing a tetraploid nucleus which divides into four diploid nuclei by meiosis and into eight haploid ascospores by "brachymeiosis". Based on descriptions in https://dx.doi.org/10.1017/S0269915X05003058 (brachymeiosis) and ISBN 978-81-259-1433-4 (p. 129; current understanding).