More than 80% of the conidia produced by two different isolates of Paracoccidioides brasiliensis, were found to be uninucleate; however, when they were incubated at 37°C and began to transform into yeast cells, they became bi- or multi-nucleated, so that when most of the conidia had already transformed into yeast cells (72–96 h), there were at least four or five nuclei per cell in approximately 80% of the conidia examined.