Solving a long-standing enigma: Myrmicinosporidium durum belongs to Blastocladiomycota, a phylum of primarily aquatic fungi.

Myrmicinosporidium durumHölldobler (1933) is a widely distributed fungal endoparasite of ants. However, little is known about its biology, ecology, or evolutionary history. Our study investigated the phylogenetics of this entomopathogenic fungus using a molecular approach. Samples of M. durum were obtained from infected Solenopsis fugax workers collected in Warsaw (Poland). Analyses of rDNA markers revealed that M. durum belongs to a phylum of primarily aquatic fungi, Blastocladiomycota. It is currently the only species from this group known to parasitise hymenopterans. Our findings have clarified this fungus' taxonomy and suggest future directions for research into its biology, ecology, and infection dynamics.