Hexadecad dissection. (A) Upper panel, stromata; lower panel, developing asci of which two contain 16 ascospores. Each ascospore is numbered according to its order in the ascus. Sixteen ascospores from a hexadecad were sequentially separated and grown on individual 100-mm malt extract agar (MEA) plates. A single colony from one ascospore was isolated and transferred individually to a 60-mm potato dextrose agar (PDA) plate to determine the spore viability, spore color, and colony morphology. (B-C) Ascospore phenotype of hexadecads from the sexual crossing of the wild isolate CBS999.97(1-1, re) with CBS999.97(1-2, wt) (n ≥ 20) or QM6a(1-2, wt) (n ≥ 10). Hexadecads were grown in constant darkness. Sixteen single-ascospore colonies were aligned sequentially according to the ascospore order. The inviable ascospores are indicated by a black circle with a cross.