Abstract
Within the genus Mallocybe, new species have been continuously discovered on a global scale, yet only few species have been reported from China. During surveys of macro-fungi diversity and taxonomy in Sichuan Province, China, two samples were collected in the forests dominated by Quercus glauca and identified as a new member of this genus, namely Mallocybe longquanensis. Morphologically, M. longquanensis is distinguished by its small-sized basidioma, light brown to yellowish-brown pileus covered with tomentose-fibrillose, ellipsoidal or ovoid basidiospores, as well as the utriform, clavate to cylindrical cheilocystidia. Multi-gene phylogenetic analysis of ITS, LSU, and rpb2 also revealed that the new taxon forms a distinct lineage within the genus Mallocybe. The detailed morphological features, color photographs, and comparisons with morphological similar taxa are provided.