Beimforde Christina, Feldberg Kathrin, Nylinder Stephan, Rikkinen Jouko, Tuovila Hanna, Dörfelt Heinrich, Gube Matthias, Jackson Daniel J, Reitner Joachim, Seyfullah Leyla J, Schmidt Alexander R
Courant Research Centre Geobiology, University of Göttingen, Goldschmidtstraße 3, 37077 Göttingen, Germany.
Systematic Botany and Mycology, Faculty of Biology, University of Munich (LMU), Menzinger Str. 67, 80638 Munich, Germany.
Mol Phylogenet Evol. 2014 Sep;78:386-98. doi: 10.1016/j.ympev.2014.04.024. Epub 2014 Apr 30.
The phylum Ascomycota is by far the largest group in the fungal kingdom. Ecologically important mutualistic associations such as mycorrhizae and lichens have evolved in this group, which are regarded as key innovations that supported the evolution of land plants. Only a few attempts have been made to date the origin of Ascomycota lineages by using molecular clock methods, which is primarily due to the lack of satisfactory fossil calibration data. For this reason we have evaluated all of the oldest available ascomycete fossils from amber (Albian to Miocene) and chert (Devonian and Maastrichtian). The fossils represent five major ascomycete classes (Coniocybomycetes, Dothideomycetes, Eurotiomycetes, Laboulbeniomycetes, and Lecanoromycetes). We have assembled a multi-gene data set (18SrDNA, 28SrDNA, RPB1 and RPB2) from a total of 145 taxa representing most groups of the Ascomycota and utilized fossil calibration points solely from within the ascomycetes to estimate divergence times of Ascomycota lineages with a Bayesian approach. Our results suggest an initial diversification of the Pezizomycotina in the Ordovician, followed by repeated splits of lineages throughout the Phanerozoic, and indicate that this continuous diversification was unaffected by mass extinctions. We suggest that the ecological diversity within each lineage ensured that at least some taxa of each group were able to survive global crises and rapidly recovered.
子囊菌门是真菌界目前最大的类群。诸如菌根和地衣等具有重要生态意义的共生关系在该类群中得以演化，它们被视为支持陆地植物演化的关键创新。迄今为止，仅有少数研究尝试使用分子钟方法来确定子囊菌谱系的起源时间，这主要是由于缺乏令人满意的化石校准数据。因此，我们评估了所有现存最古老的来自琥珀（阿尔必阶至中新世）和燧石（泥盆纪和马斯特里赫特阶）的子囊菌化石。这些化石代表了五个主要的子囊菌纲（柄锈菌纲、座囊菌纲、散囊菌纲、虫囊菌纲和茶渍菌纲）。我们从总共145个分类单元中组装了一个多基因数据集（18S核糖体DNA、28S核糖体DNA、RNA聚合酶II亚基1和RNA聚合酶II亚基2），这些分类单元代表了子囊菌门的大多数类群，并仅利用子囊菌内部的化石校准点，采用贝叶斯方法来估计子囊菌谱系的分歧时间。我们的结果表明，盘菌亚门在奥陶纪开始初步分化，随后在显生宙期间谱系多次分裂，这表明这种持续的分化并未受到大规模灭绝事件的影响。我们认为每个谱系内的生态多样性确保了每个类群中至少有一些分类单元能够在全球危机中存活并迅速恢复。
