紫距淫羊藿的地理分布新记录及形态描述

New records of Epimedium epsteinii(Berberidaceae)in Guangdong and Hubei provinces and morphologic description

关键词:  紫距淫羊藿, 新分布, 广东省, 湖北省, 居群, 形态描述

Key words:  Epimedium epsteinii Stearn, new record, Guangdong Province, Hubei Province, population, morphologic description

摘要:

淫羊藿属依据少量栽培个体命名的类群普遍存在,往往缺乏足够的野外调查和形态性状统计,对其性状变异幅度、变异式样和分类价值研究不够。紫距淫羊藿(Epimedium epsteinii)由Stearn于1997年依据引种个体命名,为掌握其资源分布及形态性状变异,该研究基于居群概念,对淫羊藿属分布区展开调查,在各分布区选择一个居群(30个体/居群)于花期进行形态观察、统计和描述。结果表明:紫距淫羊藿以往被认为狭域分布于湖南天平山,该研究调查发现广东省和湖北省均有分布,为新分布记录。此两处新分布分别位于天平山的南部和北部,将其自然分布区显著扩大。基于居群观测的形态变异较原描述更广泛。6个主要数量性状(株高、序轴长、小花数、叶长、叶宽和根茎)和花部颜色在居群间和个体间均呈现丰富的变异。生物种的分布范围并非完全连续,而是由若干个多少间断的居群组成,任何一个居群都存在不同程度的连续性变异,要更好地认识各物种,就应当足够重视这些居群系统。紫距淫羊藿的新分布记录对淫羊藿属的资源利用、扩散机制和系统地理学研究具有重要意义。

Abstract:

A considerable part of species of Epimedium were described based on a limited number of cultivated individuals. Due to the lack of adequate field investigation and morphological observation, we know little about the characters variation range, variation patterns and its taxonomic value. Indeed, the taxonomical descriptions of some species in Epimedium are probably open to questions. E. epsteinii(Berberidaceae), an endemic species of China, was collected in 1994 and then described, according to several cultivated individuals, in 1997. In order to investigate the distribution and to evaluate the morphological variation, 30 individuals per population were selected and used in the morphological observation, statistics and description. E. epsteinii is regarded as an endemic species, which was restricted distribution in the Tianpingshan Mountains of Hunan Province. However, through the extensive field investigation, it was found that the species also distributed in Nanling National Forest Park(Guangdong Province)and Jianshi County(Hubei Province). The new distribution was located in north and south of the Tianpingshan Mountains, respectively. The present report has significantly expanded the natural distribution range of E. epsteinii. Based on the ‘population' concept, extensive variation was observed among individuals and populations. Both the main quantitative traits, i.e. the plant height, inflorescence length, number of flowers, rhizome diameter, length and width of leaf, and color of flower were presented abundant variations. A correct species concept stems from a correct and thorough understanding of the nature of variation pattern of plants and its taxonomical value. Therefore, the populations not only are useful for taxonomical research, but also have great significance in contributing to a better understanding or interpretation of the variation pattern of the species. The new records of E. epsteinii in Guangdong and Hubei provinces will be useful for the resource utilization, and for further research on the spreading mechanism and phytogeography of genus Epimedium.