铁线莲属尾叶铁线莲组(毛茛科)基于形态学证据的分支系统学

选取铁线莲属 (Clematis) 尾叶铁线莲组(sect. Campanella)中37个种以及西南铁线莲组 (sect. Bebaeanthera) 中的2个种为内类群, 以Clematis alternata作为外类群, 通过对全世界10个标本馆的近2 000份腊叶标本的形态学特征统计, 选取了35个性状进行编码, 利用PAUP 4.0 beta 10 软件进行系统发育重建。通过最简约法(maximum parsimony)分析共得到182棵最简约分支树, 树长为182步, 一致性指数(CI)=0.385, 保持性指数(RI)=0.685。结果表明: (1)尾叶铁线莲组并非是一个单系类群; (2)以花序发生位置这一性状建立的sect. Bebaeanthera不能成立, 应并入尾叶铁线莲组; (3)本研究结果不支持在尾叶铁线莲组中建立subsect. Henryianae或ser. Henryianae; (4) C. ranunculoides等萼片外面具纵翅的一群植物与本组中萼片红色的种类C. lasiandra和C. dasyandra有较近的亲缘关系; (5)C. otophora、C. pogonandra、C. repens和C.barbellata等几个种聚为一支, 且支持率很高, 它们具有一系列的共衍征, 即萼片质地较厚, 花丝扁平, 宽条形, 被短柔毛, 花药被黄色短毛, 药隔先端凸起, 因此不支持建立Ser. Pogonandrae; (6)本组中非洲分布的2个种无论从形态上还是从地理分布和生境上都十分特殊, 是本组植物的特化类群。

Cladistic Analysis of Clematis sect. Campanella Tamura Cladistic Analysis of Clematis sect. Campanella Tamura

Phylogenetic relationships in Clematis sect. Campanella and related taxa were investigated with morphological data.The data matrix comprised 39 ingroup taxa, of which 2 were members of sect. Bebaeanthera. The monotypic sect. Archiclematis (Clematis alternata) was used as an outgroup. About 2 000 specimens from 10 herbaria were investigated. Vegetative as well as floral characters were used in the research. A cladistic analysis of the morphological matrix, containing 35 characters, resulted in 182 most parsimonious trees (tree length=182, CI=0.385, RI=0.685). The analysis showed that sect. Campanella is not monophyletic,because sect. Bebaeanthera is nested within sect. Campanella and closely related with Clematis otophora and its relatives. ser.Henryianae and subsect. Henryianae, established by Tamura and Johnson, are not supported by this research. Clematis ranunculoides and its allies, with 2 or 4 longitudinal wings along outer sepals, are most closely related to red-flowered species in the section (i.e., Clematis lasiandra and Clematis dasyandra. ser. Pogonandrae are not supported, because they nested with the C. otophora group). They share several synapomorphies, such as thicker sepals, flat filaments, hairy anthers, and protruding connectives. Two African species, Clematis longicauda and Clematis grandiflora, with many specialized traits, are considered as advanced groups in the section.