Abstract:

Based on 30 morphologic characters from 1500 specimens representing 13 species within the section Echinococcus, Euonymus, a numerical taxonomic study is presented. The result of cluster analysis showed that the distance between E.americanus and E.chenmoui is the nearest. Two series found by Blakelock in the section is not agreed. Some species which had confusing genetic relationship (E.hemsleyanus and E.angustatus, E.echinatus and E.subsessilis, E.hystrix and E.mengtseanus, E.acanthocarpus and E.tengyuehensis) showed far distance with each other. Characters which had obvious difference between these species were studied using analysis of variance, the result showed that there were significant difference on these characters (angle of leaf apex, length of leaf, angle between lateral vein and midrib, length of peduncle etc.). The result supported the conclusion that E.mengtseanus and E.tengyuehensis should be removed from the section. E.hemsleyanus and E.angustatus should be considered as separate species. Because there were no enough research data in crossed region, genetic relationship between E.echinatus and E.subsessilis should be researched in the future. The result of factor analysis showed that characters were independent in the experiment, 18 characters including length of leaf, angle between lateral vein and midrib, number of inflorescence branch, length of capsule (including prick) etc. were of significance for classification of section Echinococcus.

Key words: Euonymus, Echinococcus, Characters, Numerical taxonomy, Cluster analysis, Analysis of variance, Factor analysis

摘要：

通过对1500余份标本的测量和统计，结合文献和野外考察，选取了30个形态学性状，对卫矛属（Euonymus）刺果卫矛组（sect. Echinococcus）13个种进行了数量分类学分析。聚类分析结果表明，美国卫矛（E.americanus）和陈谋卫矛（E.chenmoui）的亲缘关系最近，不支持Blakelock将本组划分为两个系的观点。本组中系统位置有争议的物种：厚叶卫矛（E.hemsleyanus）与紫刺卫矛（E.angustatus）、棘刺卫矛（E.echinatus）和无柄卫矛（E.subsessilis）、刺猬卫矛（E.hystrix）和蒙自卫矛（E.mengtseanus）、刺果卫矛（E.acanthocarpus）和腾冲卫矛（E.tengyuehensis），在聚类图中显示出较远的亲缘关系，通过方差分析对这些物种间有较明显差异的性状进行进一步分析。结果表明，这些物种在叶尖角度、叶长、侧脉与主脉的夹角、花序梗长等性状上均具有显著差异。分析结果支持将蒙自卫矛与腾冲卫矛排除出刺果卫矛组，支持厚叶卫矛和紫刺卫矛作为独立的种，由于在交叉分布地域没有足够的研究资料，棘刺卫矛和无柄卫矛的系统位置有待进一步确认。因子分析结果表明，本实验所用性状间的独立性较强，叶长、侧脉与主脉的夹角、花序分支数、果实带刺的长度等18个性状在本组中具有重要的分类学意义。

关键词: 卫矛属, 刺果卫矛组, 性状, 数量分类, 聚类分析, 方差分析, 因子分析