Phylogenetics and biogeography of the neotropical fern genera Jamesonia and Eriosorus (Pteridaceae).
Phylogenetics and biogeography of the neotropical fern genera Jamesonia and Eriosorus (Pteridaceae).
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DOI：
10.3732/ajb.91.2.274
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发表时间：
2004-02
影响因子：
3
通讯作者：
P. Sánchez‐Baracaldo
中科院分区：
文献类型：
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作者：
P. Sánchez‐Baracaldo
Jamesonia和Eriosorus是两个传统上公认的新热带蕨类植物属，共同形成一个单系群。然而，这项研究的分子系统发育分析表明，这两个属本身都不是单系的，几个独立的谱系与jamesonia形态型都经历了相当近的辐射在páramo生态系统。基于18 S-26 S rDNA的核外转录间隔区（ETS）、质体基因rps 4和基因间间隔区rps 4-trnS的序列数据，产生了稳健的同源性。Jamesonia-Eriosorus复合体的进化历史和地理模式可以得出以下几点结论：（1）Jamesonia是多系的，Eriosorus是并系的;（2）所有分析都恢复了安第斯山脉的三个主要分支;（3）可以识别出两个支持良好的分支，分别对应于北方和中部的安第斯山脉;（4）安第斯辐射的姐妹分类群是巴西分类群Eriosorus myriophyllus。Jamesonia是最近适应性辐射的一个潜在例子，因为该群体的特点是形态和生态多样性，其栖息地是最近的起源。
Jamesonia and Eriosorus are two traditionally recognized fern genera in the Neotropics that together form a monophyletic group. Molecular phylogenetic analyses for this study suggest, however, that neither genus is itself monophyletic and that several independent lineages with the jamesonia morphotype have each undergone a fairly recent radiation in páramo ecosystems. A robust phylogeny was generated based on sequence data of the nuclear external transcribed spacer (ETS) of 18S-26S rDNA, the plastid gene rps4 and the intergenic spacer rps4-trnS. Several conclusions can be made concerning the evolutionary history and biogeographic patterns of the Jamesonia-Eriosorus complex: (1) "jamesonia" is polyphyletic, making "eriosorus" paraphyletic; (2) all analyses recover three major clades in the Andes; (3) two well-supported clades can be recognized, corresponding to the northern vs. central Andes; and (4) the sister taxon of the Andean radiation is the Brazilian taxon Eriosorus myriophyllus. Jamesonia is a potential example of a recent adaptive radiation because the group is characterized as being morphologically and ecologically diverse and its habitat is of recent origin.