Taxonomy and phylogeny of the Auriculariales (Agaricomycetes, Basidiomycota) with stereoid basidiocarps

Abstract

In the present study, we investigate taxonomy of the Auriculariales with effused or cupulate, persistent basidiocarps; generic and species concepts are revised based on morphological and DNA evidences. The genus Eichleriella is reinstated to embrace ten closely related species with ellipsoid-ovoid basidia, and the genus type, Eichleriella incarnata, is placed to the synonyms of Eichleriella leucophaea. Eichleriella bactriana, Eichleriella desertorum and Eichleriella sicca are described as new to science. In addition, four species earlier treated as members of Exidiopsis or Heterochaete are combined to the genus. The genus name Heteroradulum (type Radulum kmetii) is introduced for seven species with large, obconical, stipitate basidia. Of them, Heteroradulum adnatum and Heteroradulum semis are described as new. Two new genera, Amphistereum (with two species, type Eichleriella schrenkii) and Sclerotrema (monotypic, type Exidiopsis griseobrunnea), are proposed; Hirneolina (monotypic, type H. hirneoloides) and Tremellochaete (with two species, type Exidia japonica) are restored as good genera. The type species of Heterochaete, H. andina, is congeneric with Exidiopsis (type E. effusa).

<p><strong><em>Heteroradulum yunnanensis</em> <em>sp. nov. </em>(Auriculariales, Basidiomycota) evidenced by morphological characters and phylogenetic analyses in China</strong></p>

“…Bres. (1905:208), Sclerotrema Spirin & Malysheva (2017:712) and Tremellochaete (Malysheva & Spirin 2017). Our result based on the combined ITS+nLSU sequence data (Fig.…”

“…Previously, seven corticioid genera in the Auriculariales were phylogenetically studied: Amphistereum Spirin & Malysheva (2017:696), Eichleriella Bres. (1903, Exidiopsis, Heteroradulum, Hirneolina (Pat.)…”

“…Möller (1895:168) and Tremellochaete japonica (Lloyd) Raitv (1964:30). obtained from GenBank were used as outgroups to root trees following Malysheva & Spirin (2017) in the ITS+nLSU analysis (Fig. 1).…”

“…The genus was typified by H. kmetii (Bres.) Spirin & Malysheva (2017: 711) (Malysheva & Spirin 2017), which is characterized by a combination of annual or perennial, resupinate or effused-reflexed basidiomata with a leathery consistencey, hymenophore smooth to odontioid, a monomitic hyphal structure (rare dimitic) with clamp connections on generative hyphae, and the presence of cystidia, basidia narrowly ovoid to obconical, longitudinally septate with a well-developed enucleate stalk and basidiospores hyaline, thin-walled, smooth, cylindrical, acyanophilous and negative in Melzer's reagent (Malysheva & Spirin 2017). So far six species have been accepted in the genus worldwide (Berkeley 1873, Berkeley & Broome 1875, Patouillard & Lagerheim 1893, Bresadola 1897, Bodman 1953, Malysheva & Spirin 2017.…”

“…Recently, molecular studies involving Heteroradulum have been carried out (Malysheva & Spirin 2017, Malysheva et al 2018, Yuan et al 2018. Phylogenetic study of the Auriculariales with stereoid basidiocarps revealed that Heteroradulum was validated and two new species, five combinations were introduced on the base of the combined data of the nuclear ribosomal LSU and the internal transcribed spacer (ITS) regions (Malysheva & Spirin 2017). Malysheva et al (2018) revised of Protohydnum A.…”