Two new truffle species, Tuber japonicum and Tuber flavidosporum spp. nov. found from Japan

• Two new truffle species, Tuber japonicum and T. flavidosporum are described.
• T. japonicum has two-spored asci and pale yellow, irregularly reticulate ascospores.
• T. flavidosporum has one ascospore per ascus with large reticulate ornamentation.
• Phylogenetic analysis suggests T. japonicum and T. flavidosporum to be new species.

We describe and illustrate two new species, Tuber japonicum and Tuber flavidosporum, based on molecular and morphological analyses. Tuber japonicum is characterized by its two-spored asci and pale yellow irregularly reticulate ascospores. Tuber flavidosporum has one ascospore per ascus, which is similar to some related species in China, but is distinguishable by its large reticulate ornamentation. Molecular phylogenetic analysis also supports T. japonicum and T. flavidosporum as new species.