Vezdaea minima, a new species of microlichen from Japan

The genus Vezdaea consists of lichenized or alga-associated fungi and is characterized by small apothecia without exciple. Unidentified Vezdaea was collected in Japan and morphological observation was performed. The collected samples differed from any known species of the genus Vezdaea in the combination of net-like morphology of paraphyses and the size of the asci and ascospores. Fungal isolates were established from ascospores and goniocysts, and the phylogenetic analysis was performed. The isolates from ascospores and adjacent goniocysts were shown to be conspecific and grouped within the genus Vezdaea. Vezdaea minima is established to accommodate the collected fungus. Species of Vezdaea with and without net-like paraphyses were shown to be not monophyletic respectively. An algal isolate was obtained from the goniocyst, which generally contains a single algal cell, and was nested within Coccomyxa viridis clade as the result of the phylogenetic analysis. Our result indicates that the photobiont of Vezdaea needs further investigation since it has been considered as Leptosira based on a single observation.