Two new species of Aleurodiscus s.l. (Russulales, Basidiomycota) on bamboo from tropics

A new species of the genus Aleurodiscus sensu lato (Russulales, Basidiomycota) from Hachijo Island, Japan

Aleurodiscus sagittisporus sp. nov. is described and illustrated. This species is characterized by producing basidiomata with a monomitic hyphal system, clampless-septate hyphae, arrowhead-shaped, amyloid, finely verrucose basidiospores, gloeocystidia, dendrohyphidium-like branched paraphysoid hyphae, and variously shaped swelling cells in the hymenium. Phylogenetic analyses based on nuclear rDNA LSU and ITS sequences revealed that the species is distinct from the lineage of Aleurodiscus s. str. and related genera in the Aleurodiscus s. lat. clade. Basidiomata of A. sagittisporus have been collected only from dead petioles attached to living trees of Livistona chinensis var. subglobosa on Hachijo Island, Japan.

Species and genera in Aleurodiscus sensu lato as viewed from the Southern Hemisphere

Phylogenetic relationships of 12 species in Aleurodiscus sensu lato (Stereaceae, Russulales) described from the Patagonian forests of Chile and Argentina were investigated based on sequences of nuc rDNA internal transcribed spacer region ITS1-5.8S-ITS2 (ITS) and the D1-D2 domains of nuc 28S rDNA (28S). A new genus and a new species are presented, and 10 new combinations proposed. The genus Gloeosoma is shown to be phylogenetically well supported and morphologically circumscribed; it includes G. vitellinum (type species), G. mirabile, comb. nov., G. zealandicum, comb. nov., and Gloeosoma decorticans, sp. nov., which is newly described from Chile. The new genus Stereodiscus is proposed to accommodate a group of taxa characterized by an austral distribution and morphologically by smooth, thin-walled, amyloid basidiospores and a lack of gloeocystidia and acanthocystidia; three species develop Stereum-like basidiomata and two species present discoid ones. The new genus includes the species formerly known as Aleurodiscus antarcticus, A. limonisporus, A. parmuliformis, A. patagonicus, and A. triviale. Specimens of Stereodiscus parmuliformis (A. parmuliformis) from New Zealand (where it was originally described) and southern Chile are shown to be phylogenetically conspecific, which confirms its presence in Patagonia. Gloeosoma and Stereodiscus are shown to be distantly related to Aleurodiscus s. str. and other genera in Stereaceae. The new combinations Aleurocystidiellum bernicchiae, Aleurocystidiellum hallenbergii, and Acanthobasidium quilae are proposed based on morphology and phylogenetic analyses, and Aleurodiscus cerussatus is shown to be a cryptic species complex.

Four new East Asian species of Aleurodiscus with echinulate basidiospores

Four new species of Aleurodiscus sensu lato with echinulate basidiospores are described from East Asia: A.alpinus, A.pinicola, A.senticosus, and A.sichuanensis. Aleurodiscusalpinus is from northwest Yunnan of China where it occurs on Rhododendron in montane habitats. Aleurodiscuspinicola occurs on Pinus in montane settings in Taiwan and northwest Yunnan. Aleurodiscussenticosus is from subtropical Taiwan, where it occurs on angiosperms. Aleurodiscussichuanensis is reported from southwest China on angiosperms in montane environments. Phylogenetic relationships of these four new species were inferred from analyses of a combined dataset consisting of three genetic markers, viz. 28S, nuc rDNA ITS1-5.8S-ITS2 (ITS), and a portion of the translation elongation factor 1-alpha gene, TEF1.

Three new species of Aleurodiscus s.l. (Russulales, Basidiomycota) from southern China

Three new species of Aleurodiscus s.l. with corticioid basidiomata are described and illustrated from southern China based on morphological evidence and phylogenetic analyses of ITS and nrLSU sequence data. Aleurodiscusbambusinus was collected from Jiangxi Province on bamboo and is distinct by having a compact texture, simple-septate generative hyphae, abundant acanthophyses, basidia with acanthophysoid appendages and smooth basidiospores. Aleurodiscusisabellinus was collected from Yunnan Province on both angiosperm wood and bamboo and is distinct by having soft basidiomata with yellow to yellowish-brown hymenophore, yellow acanthophyses, simple-septate generative hyphae and smooth basidiospores. Aleurodiscussubroseus was collected from Guangxi Autonomous Region and Guizhou Province on angiosperm wood and is distinct by having pinkish basidiomata when fresh, clamped generative hyphae, clavate acanthophyses and echinulate basidiospores. In the phylogenetic tree, A.bambusinus and A.isabellinus were nested within the A.cerussatus group, whilst A.subroseus was clustered with A.wakefieldiae. An identification key to 26 species of Aleurodiscus s.l. in China is provided.