Malassezia is widespread and has undescribed diversity in the marine environment

There is substantial fungal diversity in marine environments where uncharacterized species may play important ecological roles. Malassezia, a genus of yeast generally associated with mammalian skins, is an example of a seemingly abundant marine fungus in ocean environments. Accumulating evidence indicates that Malassezia is widespread in the ocean. However, we know little about its diversity, role, and distribution. To address these gaps in our knowledge, we analyzed 127 marine samples collected from marine rocks, sediment, water, and various organisms, from the coasts of Hawai'i, Washington, and Massachusetts. We then used Malassezia-specific 28S primers in a nested PCR approach to amplify all present Malassezia, and performed Illumina sequencing from which we generated a possible phylogeny. Based on our phylogenetic results, we circumscribed 20 potentially novel clades that might represent new species. Our findings are consistent with Malassezia having substantial novel diversity and a high prevalence in the marine environment.