Mycosphere Essays 1: Taxonomic Confusion in the Ganoderma lucidum Species Complex

The genus Ganoderma (Ganodermataceae) has been widely used as traditional medicines for centuries in Asia, especially in China, Korea and Japan. Its species are widely researched, because of their highly prized medicinal value, since they contain many chemical constituents with potential nutritional and therapeutic values. Ganoderma lucidum (Lingzhi) is one of the most sought after species within the genus, since it is believed to have considerable therapeutic properties. In the G. lucidum species complex, there is much taxonomic confusion concerning the status of species, whose identification and circumscriptions are unclear because of their wide spectrum of morphological variability. In this paper we provide a history of the development of the taxonomic status of the G. lucidum species complex. We present a phylogeny for the G. lucidum complex based on multigene analysis with combined 5.8S-ITS rDNA, RPB1, and EF-1 alpha sequence data for 17 taxa of the complex. The taxonomic standing of these species is briefly discussed. Further clarification is, however, required. Type specimens, epitypes, reference collections, fresh collections and vouchered multigene nucleotide sequence data of more informative DNA markers should be used to determine the taxonomy of species in the G. lucidum complex.