Weststrand Stina, Korall Petra
Systematic Biology, Department of Organismal Biology, Evolutionary Biology Centre, Uppsala University, Norbyvägen 18D, SE-752 36 Uppsala, Sweden.
Systematic Biology, Department of Organismal Biology, Evolutionary Biology Centre, Uppsala University, Norbyvägen 18D, SE-752 36 Uppsala, Sweden
Am J Bot. 2016 Dec;103(12):2160-2169. doi: 10.3732/ajb.1600288. Epub 2016 Dec 20.
The lycophyte family Selaginellaceae includes approximately 750 herbaceous species worldwide, with the main species richness in the tropics and subtropics. We recently presented a phylogenetic analysis of Selaginellaceae based on DNA sequence data and, with the phylogeny as a framework, the study discussed the character evolution of the group focusing on gross morphology. Here we translate these findings into a new classification.
To present a robust and useful classification, we identified well-supported monophyletic groups from our previous phylogenetic analysis of 223 species, which together represent the diversity of the family with respect to morphology, taxonomy, and geographical distribution. Care was taken to choose groups with supporting morphology.
In this classification, we recognize a single genus Selaginella and seven subgenera: Selaginella, Rupestrae, Lepidophyllae, Gymnogynum, Exaltatae, Ericetorum, and Stachygynandrum. The subgenera are all well supported based on analysis of DNA sequence data and morphology. A key to the subgenera is presented.
Our new classification is based on a well-founded hypothesis of the evolutionary relationships of Selaginella, and each subgenus can be identified by a suite of morphological features, most of them possible to study in the field. Our intention is that the classification will be useful not only to experts in the field, but also to a broader audience.
石松科植物在全球约有750种草本植物，主要分布在热带和亚热带地区，物种丰富。我们最近基于DNA序列数据对石松科进行了系统发育分析，并以该系统发育为框架，重点从总体形态学角度探讨了该类群的性状演化。在此，我们将这些研究结果转化为一个新的分类系统。
为了提出一个可靠且实用的分类系统，我们从之前对223个物种的系统发育分析中确定了得到充分支持的单系类群，这些类群共同代表了该科在形态学、分类学和地理分布方面的多样性。在选择类群时，我们谨慎地挑选了具有支持性形态特征的类群。
在这个分类系统中，我们认可单一属——卷柏属，以及七个亚属：卷柏亚属、石上莲亚属、叶背有鳞片亚属、裸叶亚属、高大亚属、石楠状亚属和穗花亚属。基于DNA序列数据和形态学分析，这些亚属均得到了充分支持。文中还给出了亚属检索表。
我们的新分类系统基于一个关于卷柏属进化关系的有充分依据的假说，每个亚属都可以通过一系列形态特征来识别，其中大多数特征可以在野外进行研究。我们的目的是，这个分类系统不仅对该领域的专家有用，而且对更广泛的受众也有用。
