Reconstructing Krassilovia mongolica supports recognition of a new and unusual group of Mesozoic conifers
Reconstructing Krassilovia mongolica supports recognition of a new and unusual group of Mesozoic conifers
复制标题
DOI：
10.1371/journal.pone.0226779
复制
发表时间：
2020-01-15
期刊：
影响因子：
3.7
通讯作者：
Crane, Peter R.
中科院分区：
文献类型：
--
作者：
Herrera, Fabiany;Shi, Gongle;Crane, Peter R.
以前未被认识的解剖学特征的锥形鳞片的神秘的早白垩世针叶树Krassilovia mongolica包括横向取向的平列气孔的存在，这是不寻常的所有其他灭绝和现存的针叶树。相同的气孔存在于共同发生的宽，线性，多脉叶分配给Podozamites harrisii，提供证据，K。mongolica和P. harrisii是同一种已灭绝植物的球果和叶子。系统发育分析的重建Krassilovia植物的关系把它放在一个非正式的Glade，我们命名为Krassilovia分支，其中还包括Swedenborgia cryptomerioides-Podozamites schenkii，和Cycadocarpidium erdmanni-Podozamites schenkii。所有这三种植物都有线性的叶子，与大多数现存的针叶树相比相对较宽，并且也是多脉的，具有横向定向的平列气孔。我们建议，这些可能是Krassilovia分支的一般特征。平裂气孔，和其他功能，这个新的组，回忆功能的现存和化石买麻藤，提出了类似的分子数据的系统发育分析所提出的问题的系统发育同源性的针叶林空地。
Previously unrecognized anatomical features of the cone scales of the enigmatic Early Cretaceous conifer Krassilovia mongolica include the presence of transversely oriented paracytic stomata, which is unusual for all other extinct and extant conifers. Identical stomata are present on co-occurring broad, linear, multiveined leaves assigned to Podozamites harrisii, providing evidence that K. mongolica and P. harrisii are the seed cones and leaves of the same extinct plant. Phylogenetic analyses of the relationships of the reconstructed Krassilovia plant place it in an informal Glade that we name the Krassilovia Clade, which also includes Swedenborgia cryptomerioides-Podozamites schenkii, and Cycadocarpidium erdmanni-Podozamites schenkii. All three of these plants have linear leaves that are relatively broad compared to most living conifers, and that are also multiveined with transversely oriented paracytic stomata. We propose that these may be general features of the Krassilovia Clade. Paracytic stomata, and other features of this new group, recall features of extant and fossil Gnetales, raising questions about the phylogenetic homogeneity of the conifer Glade similar to those raised by phylogenetic analyses of molecular data.