A mutation that produces small (petite" > petite) anaerobic-like colonies had shown first in Yeast Saccharomyces cerevisiae and described by Boris Ephrussi and his co-workers in 1949 in Gif-sur-Yvette, France. The cells of petite colonies were smaller than those of wild-type colonies, but the term “petite” refers only to colony size and not the individual cell size.