Morphological and molecular characterization of the new aethaloid species Didymium yulii

ABSTRACTFive specimens, initially presumed to be Fuligo septicaor Mucilago crustacea, were collected from Jilin Province and the Inner Mongolia Autonomous Region in China, but all five turned out to represent a new aethaloid species, Didymium yulii. This new species is characterized by pseudocapillitia without capillitia and an aethalioid fruiting body, features that are morphologically distinct from those of any other species of Didymium. To assess the phylogenetic relationships between D. yuliiand other members of Didymiumand in the Didymiaceae, sequences from two nonoverlapping targeted portions of nuc 18S rDNA (~450 bp and ~1050 bp) and translation elongation factor 1-alpha (tef1) were obtained and analyzed. The results indicate that D. yuliiforms a single clade separate from other species of Didymiumand the clade that contains M. crustacea, which strongly supports the identification of the five specimens as a new species.