Eumycetoma is a chronic fungal infection characterised by large subcutaneous masses and the presence of sinuses discharging
coloured grains. The causative agents of black-grain eumycetoma mostly belong to the orders Sordariales and Pleosporales.
The aim of the present study was to clarify the phylogeny and taxonomy of pleosporalean agents, viz. Madurella grisea, Medicopsis
romeroi (syn.: Pyrenochaeta romeroi), Nigrograna mackinnonii (syn. Pyrenochaeta mackinnonii), Leptosphaeria senegalensis,
L. tompkinsii, and Pseudochaetosphaeronema larense. A phylogenetic analysis based on five loci was performed: the Internal
Transcribed Spacer (ITS), large (LSU) and small (SSU) subunit ribosomal RNA, the second largest RNA polymerase subunit (RPB2),
and translation elongation factor 1-alpha (TEF1) gene. In addition, the morphological and physiological characteristics were
determined. Three species were well-resolved at the family and genus level. Madurella grisea, L. senegalensis, and L. tompkinsii
were found to belong to the family Trematospheriaceae and are reclassified as Trematosphaeria grisea comb. nov., Falciformispora
senegalensis comb. nov., and F. tompkinsii comb. nov. Medicopsis romeroi and Pseudochaetosphaeronema larense were phylogenetically
distant and both names are accepted. The genus Nigrograna is reduced to synonymy of Biatriospora and therefore N. mackinnonii
is reclassified as B. mackinnonii comb. nov. Mycetoma agents in Pleosporales were phylogenetically quite diverse despite their
morphological similarity in the formation of pycnidia, except for the ascosporulating genus Falciformispora (formerly in Leptosphaeria).
Most of the species diagnosed from human mycetoma were found to be related to waterborne or marine fungi, suggesting an association
of the virulence factors with oligotrophism or halotolerance.