ABSTRACT
In the present study, fourteen Exidia-like specimens were collected from China, France, and Australia. Based on morphological characteristics and phylogenetic analyses using the internal transcribed spacer regions (ITS) and the large subunit of nuclear ribosomal RNA gene (nLSU), four species in Exidia sensu lato, including Exidia saccharina and Tremellochaete atlantica, and two new species, Exidia subsaccharina and Tremellochaete australiensis, were identified. The four species are described and illustrated in detail. E. saccharina and T. atlantica, two known species from China are reported for the first time. E. subsaccharina and T. australiensis, two new species from France and Australia, respectively are also described. E. subsaccharina is characterized by its reddish brown to vinaceous brown basidiomata, slightly papillate hymenial surface, and narrowly allantoid basidiospores without oil drop measuring 12.5-17.5 × 4.2-5.5 µm. It differs from the similar species, E. saccharina, by distinctly larger basidiospores (12.5-17.5 × 4.2-5.5 vs. 10-14.2 × 3.2-4.5 µm). Tremellochaete australiensis is characterized by its white to grayish blue basidiomata, obviously and densely papillate hymenial surface, and allantoid basidiospores with oil drop measuring 13.8-16.2 × 4.8-6.5 µm. It also can be distinguished from the similar species, T. atlantica and T. japonica, by its distinctly larger basidiospores (13.5-17.8 × 4-5.2 vs. 10-11.8 × 4-4.8 µm in T. atlantica; 9.4-11.8 × 3.5-4.2 µm in T. japonica).
ABSTRACT
Auricularia has a worldwide distribution and is very important due to its edibility and medicinal properties. Morphological examinations and multi-gene phylogenetic analyses of 277 samples from 35 countries in Asia, Europe, North and South America, Africa, and Oceania were carried out. Phylogenetic analyses were based on ITS, nLSU, rpb1, and rpb2 sequences using methods of Maximum Likelihood and Bayesian Inference analyses. According to the morphological and/or molecular characters, 37 Auricularia species were identified. Ten new species, A. camposii and A. novozealandica in the A. cornea complex, A. australiana, A. conferta, A. lateralis, A. pilosa and A. sinodelicata in the A. delicata complex, A. africana, A. srilankensis, and A. submesenterica in the A. mesenterica complex, are described. The two known species A. pusio and A. tremellosa, respectively belonging to the A. mesenterica complex and the A. delicata complex, are redefined, while A. angiospermarum, belonging to the A. auricula-judae complex, is validated. The morphological characters, photos, ecological traits, hosts and geographical distributions of those 37 species are outlined and discussed. Morphological differences and phylogenetic relations of species in five Auricularia morphological complexes (the A. auricula-judae, the A. cornea, the A. delicata, the A. fuscosuccinea and the A. mesenterica complexes) are elaborated. Synopsis data on comparisons of species in the five complexes are provided. An identification key for the accepted 37 species is proposed.
