Microbotryum crypticum, a new anther smut fungus on Silene miqueliana from Japan.

A new anther smut fungus, Microbotryum crypticum is described based on specimens collected from the Japanese endemic plant, Silene miqueliana (Caryophyllaceae) in Osaka Prefecture, as well as from herbarium specimens of S. miqueliana preserved at the National Museum of Nature and Science (TNS) in Japan. Microbotryum crypticum is phylogenetically distinct from other anther smut fungi reported on Silene species and has relatively small spores compared to previously described Microbotryum species. Host preference further supports this new species. The presence of infected S. miqueliana plants in both herbarium and fresh specimens suggests that M. crypticum is widely distributed in Japan.