Abstract
Ophiocordyceps tianshanensis is a novel species introduced from Xinjiang Uygur Autonomous Region, China. The taxon was discovered with its sexual and asexual specimens on Camponotus japonicus (Formicidae) under the bark of humid and decayed wood of Picea schrenkiana. With irregularly distorted stromata and distributed in the cold and high-altitude Tianshan Mountains, the species can be separated from other extant Ophiocordyceps species. Morphological and multigene phylogenetic analyses support its novelty. We provide additional ecological data on this cordyceps species from northwestern China.