A total evidence approach using palynological characters to infer the complex evolutionary history of the Asian Impatiens (Balsaminaceae)
A total evidence approach using palynological characters to infer the complex evolutionary history of the Asian Impatiens (Balsaminaceae)
复制标题
DOI：
10.1002/tax.612007
复制
发表时间：
2012-04-01
期刊：
影响因子：
3.4
通讯作者：
Huysmans, Suzy
中科院分区：
文献类型：
--
作者：
Janssens, Steven B.;Wilson, Yi Song;Huysmans, Suzy
本研究有助于更好地了解凤仙花属的主要孢粉学趋势，在被子植物中最大的属之一，并评估花粉形态特征的系统发育的有用性。利用光学显微镜和扫描电镜对115种亚洲种的花粉形态多样性进行了研究，并利用贝叶斯推断和贝叶斯后验特征映射以及简约特征优化在系统发育框架中进行了分析。尽管凤仙花的年龄相当年轻，其辐射非常迅速，但可以观察到显着的孢粉变异性。凤仙花属的祖先花粉类型是三角形的、三孔的花粉粒，具有网状的六线排列，随后演变成凤仙花属的主要花粉类型：四孔的、矩形的花粉粒，具有网状的六线排列。最近多样化的亚洲分支的特征是从4孔到3孔的几个逆转和从网状到微网状的性线排列的变化。此外，在最近多样化的亚洲谱系中可以观察到花粉视图的差异，从圆形，四边形，椭圆形到亚椭圆形和矩形。虽然有些花粉形态特征似乎是homoplasious，其他人有助于提高分辨率的属中的一些遗传学上有问题的谱系。
The present study contributes to a better understanding of major palynological trends in Impatiens, one of the largest genera in angiosperms, and evaluates the phylogenetic usefulness of pollen morphological characters in the genus. The pollen morphological diversity of 115 Asian species of the genus was investigated using light microscopy and scanning electron microscopy and analyzed in a phylogenetic framework using Bayesian inference and Bayesian posterior character mapping as well as parsimony character optimization. Despite the rather young age of Impatiens and its extremely rapid radiation, a striking palynological variability could be observed. The ancestral pollen type in Impatiens is a triangular, tri-aperturate pollen grain with reticulate sexine ornamentation, which subsequently evolved into the main Impatiens pollen type: a 4-aperturate, rectangular pollen grain with a reticulate sexine ornamentation. The most recently diversified Asian clades are characterized by several reversions from 4-aperturate to 3-aperturate and changes in sexine ornamentation from reticulate to microreticulate sexine ornamentation. Also differences in pollen view can be observed amongst the most recently diversified Asian lineages ranging from circular, quadrangular, elliptic to sub-elliptic and rectangular. Although some pollen morphological characters seem to be homoplasious, others help to improve the resolution of some phylogenetically problematic lineages in the genus.