Departamento de Biología y Geología, Universidad Rey Juan Carlos, E-28933 Móstoles, Spain.
Mol Phylogenet Evol. 2011 Oct;61(1):12-28. doi: 10.1016/j.ympev.2011.05.014. Epub 2011 May 31.
The Tremellomycetes (Agaricomycotina, Basidiomycota, Fungi) are a nutritionally heterogeneous group comprising saprotrophs, animal parasites, and fungicolous species (fungal-inhabiting, including lichen-inhabiting). The relationships of many species, particularly those with a lichenicolous habit, have never been investigated by molecular methods. We present a phylogeny of the Tremellomycetes based on three nuclear DNA ribosomal markers (nSSU, 5.8S and nLSU), representing all main taxonomic groups and life forms, including lichenicolous taxa. The Cystofilobasidiales, Filobasidiales, Holtermanniales, and Tremellales (including the Trichosporonales) are recovered as monophyletic, but this is not the case for the Tremellomycetes. We suggest, however, that the Cystofilobasidiales tentatively continue to be included in the Tremellomycetes. As currently circumscribed, the Filobasidiaceae, Sirobasidiaceae, Syzygosporaceae and Tremellaceae are non-monophyletic. Cuniculitremaceae, Sirobasidiaceae and Tetragoniomycetaceae are nested within Tremellaceae. The lichenicolous species currently included within the Tremellomycetes belong in this group, distributed across the Filobasidiales and Tremellales. Lichen-inhabiting taxa do not form a monophyletic group; they are distributed in several clades and sometimes intermixed with taxa of other nutritional habits. Character state reconstruction indicates that two morphological traits claimed to characterize groups in the Tremellomycetes (the basidium habit and basidium septation) are highly homoplastic. Comparative phylogenetic methods suggest that the transitions between single and catenulate basidia in the Tremellales are consistent with a punctuational model of evolution whereas basidium septation is likely to have evolved under a graduational model in the clade comprising the Holtermanniales, Filobasidiales, and Tremellales.
外生菌根真菌（担子菌门，担子菌纲，真菌）是一个营养异质的群体，包括腐生菌、动物寄生虫和真菌共生种（真菌栖息的，包括地衣栖息的）。许多物种的关系，特别是那些具有地衣共生习性的物种，从未通过分子方法进行过研究。我们基于三个核 DNA 核糖体标记（nSSU、5.8S 和 nLSU），代表所有主要的分类群和生活形式，包括地衣共生类群，提出了外生菌根真菌的系统发育。Cystofilobasidiales、Filobasidiales、Holtermanniales 和 Tremellales（包括 Trichosporonales）被恢复为单系，但外生菌根真菌不是这样。然而，我们建议暂时将 Cystofilobasidiales 归入外生菌根真菌。目前定义的 Filobasidiaceae、Sirobasidiaceae、Syzygosporaceae 和 Tremellaceae 不是单系的。Cuniculitremaceae、Sirobasidiaceae 和 Tetragoniomycetaceae 嵌套在 Tremellaceae 中。目前归入外生菌根真菌的地衣共生种属于该组，分布在 Filobasidiales 和 Tremellales 中。地衣栖息的类群没有形成一个单系群；它们分布在几个分支中，有时与其他营养习性的类群混合在一起。性状状态重建表明，被认为是外生菌根真菌中特征的两个形态特征（担子菌习性和担子菌分隔）具有高度的同形性。比较系统发育方法表明，Tremellales 中单链和连锁担子的转变与一个点状进化模型一致，而 Holtermanniales、Filobasidiales 和 Tremellales 分支中担子分隔可能是在一个渐变进化模型下进化的。
