Importance of Resolving Fungal Nomenclature: the Case of Multiple Pathogenic Species in the Cryptococcus Genus

Cryptococcosis is a major fungal disease caused by members of the
Cryptococcus gattii and Cryptococcus neoformans species complexes. After more than
15 years of molecular genetic and phenotypic studies and much debate, a proposal
for a taxonomic revision was made. The two varieties within C. neoformans were
raised to species level, and the same was done for five genotypes within C. gattii. In
a recent perspective (K. J. Kwon-Chung et al., mSphere 2:e00357-16, 2017, https://doi
.org/10.1128/mSphere.00357-16), it was argued that this taxonomic proposal was
premature and without consensus in the community. Although the authors of the
perspective recognized the existence of genetic diversity, they preferred the use of the
informal nomenclature “C. neoformans species complex” and “C. gattii species complex.” Here we highlight the advantage of recognizing these seven species, as ignoring
these species will impede deciphering further biologically and clinically relevant differences between them, which may in turn delay future clinical advances.