To investigate the evolutionary diversification and morphological evolution of grass supertribe Poodae (subfam. Pooideae, Poaceae) we conducted a comprehensive molecular phylogenetic analysis including representatives from most of its accepted genera. We focused on generating a DNA sequence dataset of plastid matK gene–3′trnK exon and trnL‐trnF regions and nuclear ribosomal (nr) ITS1–5.8S gene–ITS2 and ETS that was taxonomically overlapping as completely as possible (altogether 257 species). The idea was to infer whether phylogenetic trees or certain clades based on plastid and nrDNA data correspond with each other or discord, revealing signatures of past hybridization. The datasets were analysed separately, in combination, by excluding taxa with discordant placements in the individual gene trees and with duplication of these taxa in a way that each duplicate has only one data partition (plastid or nrDNA). We used maximum likelihood, maximum parsimony and Bayesian approaches. Instances of severe conflicts between the phylogenetic trees derived from both datasets, some of which have been noted earlier, point to hybrid origin of several lineages such as the ABCV clade encompassing several subtribes and subordinate clades, subtribes Airinae, Anthoxanthinae, Antinoriinae, subtr. nov., Aristaveninae, Avenulinae, subtr. nov., Helictochloinae, subtr. nov., Holcinae, Phalaridinae, Scolochloinae, Sesleriinae, Torreyochloinae and genera Arctopoa, Castellia, Graphephorum, Hyalopodium, Lagurus, Macrobriza, Puccinellia plus Sclerochloa, Sesleria, Tricholemma, Tzveleviochloa, etc. ‘Calamagrostis’ flavens appears to be an intergeneric hybrid between Agrostis and Calamagrostis. Analyses excluding all lineages with demonstrably cytonuclear discordance revealed three supported main clades within Poodae that were present in both the plastid and nrDNA trees. They fully corresponded in their delineation but were phylogenetically differently arranged, pointing to hybrid origin of one of them. We propose to consider these main clades in classification as separate tribes Aveneae, Poeae s.str. and Festuceae with a phylogenetic arrangement of Aveneae(Poeae,Festuceae) in plastid versus Festuceae(Aveneae,Poeae) in nrDNA trees. Phylogenetic incongruence of the plastid and nuclear markers extends across all hierarchical taxonomic levels of Poodae, ranging from species (not studied here) to genera, subtribes and tribes, therefore the deepest taxonomic levels, emphasizing the enormous significance of reticulate evolution in this large group of grasses. A partly revised classification is presented, including the introduction of a new tribe Festuceae and a re‐instatement of tribe Aveneae. Following a comparatively narrow delineation of preferably monophyletic subtribes, Antinoriinae, Avenulinae, Brizochloinae, Helictochloinae and Hypseochloinae are described as new. New genera are Arctohyalopoa and Hyalopodium. New combinations are Anthoxanthum glabrum subsp. sibiricum, A. nitens subsp. kolymense, Arctohyalopoa ivanovae, A. jurtzevii, A. lanatiflora, A. momica, Colpodium biebersteinianum, C. kochii, C. pisidicum, C. trichopodum, C. verticillatum, Dupontia fulva, Festuca masafuerana, F. robinsoniana, Graphephorum canescens, G. cernuum, Hyalopodium araraticum, Paracolpodium baltistanicum, Parapholis cylindrica, P. ×pauneroi. Festuca dolichathera and F. masatierrae are new names.

中文翻译：

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系统发育谱系和杂种的作用作为草超族Poodae进化的驱动力

为了调查禾本科超支植物Poodae（亚科。Pooideae，Poaceae）的进化多样性和形态进化，我们进行了全面的分子系统发育分析，包括其大部分公认属的代表。我们专注于生成质体matK基因–3'trnK外显子和trnL-trnF的DNA序列数据集区域和核糖体（nr）ITS1-5.8S基因-ITS2和ETS在分类学上尽可能完全重叠（共257种）。想法是根据质体和nrDNA数据推断系统发育树或某些进化枝是否彼此对应或不一致，从而揭示过去杂交的特征。通过排除在单个基因树中具有不一致位置的分类单元和这些分类单元的重复，分别对每个数据集进行组合分析，以确保每个重复项仅具有一个数据分区（质体或nrDNA）。我们使用了最大似然，最大简约和贝叶斯方法。来自这两个数据集的系统发育树之间存在严重冲突的情况，其中一些已经在前面提到过，指向多个谱系的杂种起源，例如ABCV进化枝包含多个亚部落和从属进化枝，Airinae，Anthoxanthinae，Antinoriinae，subtr等亚部落。11月，Aristaveninae，Avenulinae，subtr。十一月，Helictochloinae，subtr。十一月，Hol科，Ph科，col科，Se科，y科和属Arctopoa，Castellia，Graphephorum，Hyalopodium，Lagurus，Macrobriza，Puccinellia加上Sclerochloa，Sesleria，Tricholemma，Tzveleviochloa等。“ Calamagrostis ”黄酮似乎是Agrostis和Calamagrostis之间的属间杂种。。分析排除了具有明显核细胞核不一致性的所有谱系，发现在质体和nrDNA树中都存在Poodae中三个支持的主要进化枝。它们的轮廓完全对应，但系统发育上的排列不同，指向其中之一的杂种起源。我们建议将这些主要进化枝分类为独立的部落Aveneae，Poeae s.str。质体中的Aveneae（Poeae，Festuceae）和nrDNA树中的Festuceae（Aveneae，Poeae）的亲缘关系最接近。质体和核标记物的系统发育不一致性遍及Poodae的所有分层分类学水平，范围从物种（此处未研究）到属，亚部落和部落，因此是最深的分类学水平，强调了网状进化在这一大类草丛中的巨大意义。提出了部分修订的分类，包括引入了新的部落Festuceae和恢复了Aveneae部落。在较窄地描述了优选的单系亚群之后，将新的Antinoriinae，Avenulinae，Brizochloinae，Helictochloinae和Hypseochloinae描述为。新属弧菌和透明质酸。新的组合是花椒花序亚种。苍耳，A.鲷亚种。kolymense，Arctohyalopoa ivanovae，A. jurtzevii，A. lanatiflora，A. momica，Colpodium biebersteinianum，C. kochii，C。pisidicum，C. trichopodum，C. verticillatum，Dupontia叶霉病菌，高羊masafuerana，F. robinsoniana，Graphephorum藜，G. cernuum，Hyalopodium araraticum，Paracolpodium baltistanicum，假牛鞭草属白茅，P.×pauneroi。Festuca dolichathera和F. masatierrae是新名称。