Phylogeny, taxonomy and life cycle of Diderma brasiliensis (Physarales, Didymiaceae): a new species of myxomycete

Diderma brasiliensis was found during a myxodiversity survey in Central Brazil, occurring abundantly on decomposing fallen trunks, leaf litter, and on the stems and leaves of the climbing plant Epipremnum aureum . It has globose to subglobose sporophores with reticulate spores and tortuous capillitia with nodular insertions, the latter two being very distinctive features of the species. In addition to these unique morphological traits, the proposal of this new species is phylogenetically supported by the 18S rRNA and mtSSU DNA regions. We also investigated its life cycle and cultivation strategies, recording the different stages of development and behavior, and we report a possible predatory interaction between the plasmodium of D. brasiliensis and the fungus Fusarium cf. decemcellulare. Although it shares similarities with other species of the genus, such as D. cor-rubrum , D. crustaceum , and D. subdictyospermum , D. brasiliensis is distinguished by the shape of its sporophore and capillitium, characterized by the presence of amorphous nodules and deeply reticulated spores. This study expands the knowledge of Neotropical myxomycetes and provides new insights into cultivation methods and ecological interactions.