Ascospores

Ascospores are the sexual spores formed by members of the Ascomycota. These spores are usually found in outdoor air samples during wet weather and may be introduced indoors. Ascospores are suspected allergens but have not been well studied (see Chaetomium). Ascospores are produced within a sac-like structure called an ascus. Depending on the species, ascospores vary greatly in size, shape, color, and number of cells. One feature in common is the absence of any attachment scars since they are formed within an ascus. See Ascomycota for additional details.