NEW SPECIES OF GENUS TYROMYCES FROM CHINA

The genus Tyromyces was established by Karsten in 1881. During the past hundred years many taxonomists were of different opinions on the concept of this genus. In this paper the. new generic concept of the genus is adopted. The generic characteristics are as follows: fresh fruitbody soft, separable and succulent; context fleshy, homogenous, after drying fragile, easily powdery and caseous. Hyphal system monomitic or dimitic. If dimitic it consists of generative hyphae and binding or skeletal hyphae. The hyphal system mentioned here is only included in the context and the tramal hyphae not treated. The spores of each species are not treated with chemicals because they are very rare, not easily to be found in dried specimens. Almost all of the fungi classified at present to this genus are saprophytes decaying wood of dead deciduous and coniferous trees. Many of these fungi cause brown rot of wood and some ones are destroyers of the standing and down timber. In 1886 the French mycologist L. Quelet, established the genus Leptoporus. Many mycologists consider that the two genera have the same generic delimitation. According to the studies of Donk (1960) it is better to use Tyromyces with Polyporus chioneus Fr. as the type species based on the rule of priority of nomenclature. From China Teng (1964) reported 18 species and Tai (1979) recorded 24 species. Among them the hyphal system of certain species is trimitic and, therefore should be excluded from the genus. With this new generic concept of Tyromyces, the species of the genus from China have been restudied. In the present paper 22 species have been identified, of which 6 are new records and 3 as new species (Tyromyces armeniacus, Tyromyces imbricatus, Tyromyces tibeticus). Each new species is fully described in Latin and Chinese. All the materials are deposited in the Mycological Herbarium of Institute of Microbiology, Academia Sinica, Beijing.