CBS-KNAW Fungal Biodiversity Centre, Uppsalalaan 8, 3584 CT Utrecht, The Netherlands;
Persoonia. 2009 Dec;23:99-118. doi: 10.3767/003158509X479487. Epub 2009 Oct 29.
Many fungal genera have been defined based on single characters considered to be informative at the generic level. In addition, many unrelated taxa have been aggregated in genera because they shared apparently similar morphological characters arising from adaptation to similar niches and convergent evolution. This problem is aptly illustrated in Mycosphaerella. In its broadest definition, this genus of mainly leaf infecting fungi incorporates more than 30 form genera that share similar phenotypic characters mostly associated with structures produced on plant tissue or in culture. DNA sequence data derived from the LSU gene in the present study distinguish several clades and families in what has hitherto been considered to represent the Mycosphaerellaceae. In some cases, these clades represent recognisable monophyletic lineages linked to well circumscribed anamorphs. This association is complicated, however, by the fact that morphologically similar form genera are scattered throughout the order (Capnodiales), and for some species more than one morph is expressed depending on cultural conditions and media employed for cultivation. The present study shows that Mycosphaerella s.s. should best be limited to taxa with Ramularia anamorphs, with other well defined clades in the Mycosphaerellaceae representing Cercospora, Cercosporella, Dothistroma, Lecanosticta, Phaeophleospora, Polythrincium, Pseudocercospora, Ramulispora, Septoria and Sonderhenia. The genus Teratosphaeria accommodates taxa with Kirramyces anamorphs, while other clades supported in the Teratosphaeriaceae include Baudoinea, Capnobotryella, Devriesia, Penidiella, Phaeothecoidea, Readeriella, Staninwardia and Stenella. The genus Schizothyrium with Zygophiala anamorphs is supported as belonging to the Schizothyriaceae, while Dissoconium and Ramichloridium appear to represent a distinct family. Several clades remain unresolved due to limited sampling. Mycosphaerella, which has hitherto been used as a term of convenience to describe ascomycetes with solitary ascomata, bitunicate asci and 1-septate ascospores, represents numerous genera and several families yet to be defined in future studies.
许多真菌属是基于被认为在属级水平上具有信息性的单一特征定义的。此外，许多不相关的分类群被聚集在属中，因为它们具有明显相似的形态特征，这些特征是由于适应相似的生态位和趋同进化而产生的。这种问题在 Mycosphaerella 中得到了很好的说明。在其最广泛的定义中，这个主要感染叶片的真菌属包含了 30 多个形式属，这些形式属具有相似的表型特征，主要与在植物组织或培养中产生的结构有关。本研究中从 LSU 基因获得的 DNA 序列数据将迄今为止被认为代表 Mycosphaerellaceae 的几个分支和科区分开来。在某些情况下，这些分支代表可识别的单系谱系，与定义明确的无性型相关。然而，这种关联很复杂，因为形态相似的形式属散布在整个目（Capnodiales）中，而且对于一些物种，根据培养条件和使用的培养基，会表达一种以上的形态。本研究表明，Mycosphaerella s.s. 最好限制在具有 Ramularia 无性型的分类群中，而 Mycosphaerellaceae 中的其他定义明确的分支代表 Cercospora、Cercosporella、Dothistroma、Lecanosticta、Phaeophleospora、Polythrincium、Pseudocercospora、Ramulispora、Septoria 和 Sonderhenia。Teratosphaeria 属容纳具有 Kirramyces 无性型的分类群，而在 Teratosphaeriaceae 中支持的其他分支包括 Baudoinea、Capnobotryella、Devriesia、Penidiella、Phaeothecoidea、Readeriella、Staninwardia 和 stenella。具有 Zygophiala 无性型的 Schizothyrium 属被支持为属于 Schizothyriaceae，而 Dissoconium 和 Ramichloridium 似乎代表一个独特的科。由于采样有限，几个分支仍然未解决。Mycosphaerella 迄今为止一直被用作一个方便的术语，用来描述具有单个子囊壳、双壁子囊和 1 个隔膜的子囊菌，代表了许多尚未在未来研究中定义的属和几个科。
