ABSTRACT

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.

摘要

基于 nuc rDNA 内部转录间隔区 ITS1-5.8S-ITS2 (ITS) 和 D1-D2 结构域的序列研究了智利和阿根廷巴塔哥尼亚森林中描述的 12 种Aleurodiscus sensu lato (Stereaceae, Russulales)的系统发育关系nuc 28S rDNA (28S)。提出了一个新属和一个新种，并提出了10个新组合。Gloeosoma属被证明在系统发育上得到很好的支持并且在形态上受到限制。它包括G. vitellinum（类型种）、G. mirabile、comb。十一月，G. zealandicum，梳子。十一月，和Gloeosoma corticans， sp。nov.，这是从智利新描述的。新属Stereodiscus被提议容纳一组以南方分布为特征的分类群，形态上由光滑、薄壁的淀粉样担孢子和缺乏粘囊虫和棘囊虫组成；三个物种发展出类似立体的担子体，两个物种呈现盘状担子体。新属包括以前称为Aleurodiscus antarcticus、A. limonisporus、A. parmuliformis、A. patagonicus和A. triviale的物种。来自新西兰（最初描述它的地方）和智利南部的Stereodiscus parmuliformis ( A. parmuliformis ) 的标本显示在系统发育上是同种的，这证实了它在巴塔哥尼亚的存在。胶质瘤和Stereodiscus被证明与Aleurodiscus s 的亲缘关系较远。海峡 和菊科的其他属。基于形态学和系统发育分析提出了新的组合Aleurocystidiellum bernicchiae、Aleurocystidiellum hallenbergii和Acanthobasidium quilae ，并且Aleurodiscus cerussatus被证明是一个神秘的物种复合体。