Biology Department, Colorado College, 14 E. Cache La Poudre, Colorado Springs, Colorado 80903 USA;
Am J Bot. 2004 Mar;91(3):474-89. doi: 10.3732/ajb.91.3.474.
A well-supported phylogeny is presented from both chloroplast DNA (the trnL/F region) and two regions of nuclear rDNA (ITS [internal transcribed spacer] and ETS [external transcribed spacer]) with nearly complete sampling for Mimulus (Phrymaceae) in western North America. Three separate genera are derived from within the clade that contains all the Mimulus species in western North America. The taxonomic status of the proposed sections of Mimulus and the relationships of many taxonomically difficult species are considered with observations on morphological evolution. Discordance between data sources provides support for the hypothesis that M. evanescens is a hybrid between M. latidens and M. breviflorus. In two major clades (Eunanus and Diplacus), patterns of genetic variation do not match the current taxonomy. The clustering of taxa in Eunanus is strongly associated with geographic distributions. Mimulus aurantiacus sensu Thompson, M. nanus, and M. floribundus are found to be progenitor species to other species that appear to be derived from within them. Polyploidy and aneuploidy events are clustered near the tips of the phylogeny. Thus, these two mechanisms are concluded to have played a relatively small role in the evolution of persistent lineages in Mimulus. The phylogenetic distribution of rare taxa is also examined.
从叶绿体 DNA（trnL/F 区）和核 rDNA 的两个区域（ITS[内部转录间隔区]和 ETS[外部转录间隔区]）获得了对北美西部几乎所有金光菊属（玄参科）进行了充分采样的系统发育。从包含北美西部所有金光菊属物种的分支中衍生出了三个单独的属。用形态进化的观察结果来考虑拟节和许多分类困难物种的关系。不同数据源之间的不匹配为 M. evanescens 是 M. latidens 和 M. breviflorus 之间的杂种这一假设提供了支持。在两个主要分支（Eunanus 和 Diplacus）中，遗传变异模式与当前分类法不匹配。Eunanus 中分类群的聚类与地理分布强烈相关。M. aurantiacus sensu Thompson、M. nanus 和 M. floribundus 被发现是其他似乎从它们中衍生而来的物种的祖种。多倍体和非整倍体事件聚集在系统发育树的末端附近。因此，这两种机制被认为在金光菊属持久谱系的进化中发挥了相对较小的作用。还检查了稀有分类群的系统发育分布。
