中国金粟兰属植物的形态多样性及地理分布

Morphological diversity and geographical distribution of Chloranthus in China

金粟兰属(Chloranthus Swartz)是研究被子植物起源和早期演化的关键类群之一,部分种类被广泛地栽培和使用。虽然前人已对该属植物的形态、地理分布、分类、系统发育、化石和化学成分等开展了丰富的研究,但是通过作者持续广泛的调查研究发现,以往对该属植物形态多样性、生活型和地理分布的认识仍不充分,且在该属植物中还存在分类观点不统一、名实混淆、沿用错误分类信息等问题。该研究在广泛查阅标本资料和长期野外调查的基础上,对金粟兰属植物的形态多样性、生活型和地理分布格局进行了较为全面的描述。结果表明:在形态方面,金粟兰属内花部器官尤其药隔形态在种间呈多样性而种内相对稳定,是物种划分最有效的分类性状,其中网脉金粟兰药隔形态变异较大,疑为复合群;在生活型方面,狭叶金粟兰与网脉金粟兰为常绿草本,区别于该属其他常绿亚灌木以及地上部分每年秋冬季节枯萎的多年生草本种类;在地理与生境分布方面,验证了金粟兰属内最近缘的4个长药隔草本物种间的确呈显著水平替代分布格局,而一直被认为只分布在湖北宜昌和重庆奉节等地的狭叶金粟兰却在贵州亦有分布。该研究结果不仅丰富了对中国金粟兰属植物的形态多样性、生活型、地理和生境分布特点等方面的认识,而且为正确划分和鉴别金粟兰属植物不同种类提供了更详实的依据,同时还为进一步深入研究该属植物物种的形成、演化和特殊分布格局的成因奠定基础,为这一类植物资源安全地可持续开发利用提供了保障。

Chloranthus Swartz is one of the key group for studying the origin and early evolution of angiosperms and some of the taxa have been widely cultivated or utilized.Although previous researchers have carried out abundant studies on its morphology,distribution,taxonomy,phylogeny,fossils and chemical constituents.However,our persistent and extensive investigations showed that the previous documents of the morphological diversity,habit and geographical distribution in the genus were still largely incomplete,and some problems remained such as discordant classification treatments,falsely identification,and following the wrong taxonomic treatment and so on.On the basis of extensively referring to the deposited specimens and long-term field survey,in this study,we describe the morphological diversity,habit and geographical distribution of Chloranthus in a more comprehensive and elaborate way.Morphologically,the traits of the flowers especially the anther connectives are diverse among species but relatively stable within species which are the most effective characters in interspecific differentiation,and large variations of the anther connectives were found among the populations in C.nervosus which implied that they would be species complex.On habit,C.angustifolius and C.nervosus are perennial"evergreen herbs",which differ from the two other evergreen subshrub species and the rest perennials the aboveground plant organs of which wither annually in autumn and/or in winter.On geographic distribution,it is verified that there display definite horizontal displacements of the distributional ranges(pairwise neighboring but slightly or never overlapping in distribution or parapatric distribution)among the four closely-related species with long anther connectives;and C.angustifolius is also distributed in Guizhou,beyond the documented known distribution areas of in Hubei and Chongqing.This study not only enriches and improves the understanding of morphological diversity,habit,geographical distribution of Chloranthus taxa in China,but also provides more detailed and robust evidence for correct identification and classification of different species in Chloranthus,serving as the foundation for future in-depth studies on speciation,evolution and underlying causes of the special distribution patterns in the genus,and ensuring the safe and sustainable development and utilization of these important plant resources.