中国柳属两个新记录种

Two newly recorded species of Salix from China

关键词:  中国东北，被子植物，柳属，新记录，物种多样性

Key words:  Northeast China, angiosperms, Salix, new records, species diversity

摘要:

本研究通过对中国东北地区柳属（Salix L.）植物种群的全面调查，结合国内外相关分类学文献的深入研究和多所标本馆馆藏标本的详细比对，首次报道了2个中国柳属新记录种，分别为灰毛柳[Salix sericeo-cinerea Nakai]和乌登柳[Salix udensis Trautv. & C. Meyer]。灰毛柳为典型的高山矮灌木（高0.5~1.8 m），其显著特征包括：叶片为倒卵形，成熟叶片边缘具明显的白色丝状长柔毛，花序基部具4~8枚小叶，以及花柱极显著；乌登柳则为中型灌木（高3~5 m），主要鉴别特征为成熟叶呈狭倒卵形，柱头深裂至花柱中部以下。研究不仅提供了这两个新记录种的完整形态学描述、精确的地理分布信息（灰毛柳分布于黑龙江五常凤凰山，乌登柳见于黑龙江兴凯湖及内蒙古东北部）、凭证标本记录（标本现存于北京林业大学博物馆标本室），还通过细致的比较形态学分析阐明了其与近缘种的关键区分形态，并附有高清物种图版。此外，基于种群水平的形态稳定性研究，进一步验证了这两个分类单元的分类学地位。本研究不仅填补了中国柳属植物区系记录的空白，也为中国东北地区植物多样性研究提供了重要的本底资料。

Abstract:

This study presents the first confirmed records of two willow species, Salix sericeo-cinerea Nakai and Salix udensis Trautv. & C. Meyer in China, based on an integrative approach combining extensive field investigations, critical literature review, and comprehensive herbarium specimen examinations. The research was conducted to clarify the taxonomic status, morphological characteristics, and geographical distribution of these previously undocumented species in China. Materials and methods involved: (1) Systematic field surveys across Northeast China (2021—2024), with particular emphasis on population-level morphological variations during both flowering and vegetative stages; (2) Exhaustive analysis of taxonomic literature, including original descriptions and regional floras; (3) Detailed comparisons of a substantial number of herbarium specimens, including type materials accessed through international collaborations and digital repositories. The principal results were as follows: (1) Salix sericeo-cinerea was identified as an alpine dwarf shrub (0.5-1.8 m tall) characterized by obovate leaves with margins conspicuously adorned by white silky villous hairs, catkins bearing 4-8 small basal leaves, and remarkably prominent styles. These diagnostic features provide clear distinctions from its morphologically similar congener, Salix taraikensis Kimura; (2) Salix udensis was recognized as a medium-sized shrub (3~5 m tall) with narrowly obovate leaves and uniquely deeply cleft stigmas (extending below the midpoint of the styles), providing reliable diagnostic characters to separate it from the widespread Salix sachalinensis F. Schmidt; (3) Comprehensive morphological descriptions were provided, supported by detailed illustrations and voucher specimens (deposited at BJFC), along with precise distribution data; (4) Ecological observations revealed that Salix sericeo-cinerea predominantly grows in high-altitude open slopes (1 400~1 700 m), while Salix udensis occurs in lowland wetland habitats near the China-Russia border region. This study unequivocally confirms the existence of Salix sericeo-cinerea and Salix udensis in China, representing significant additions to the diversity of Salix in the country. The findings highlight the importance of thorough taxonomic revisions and targeted field surveys in understudied regions. Moreover, the research establishes a solid foundation for future studies on the phylogeny, biogeography, and conservation of these newly recorded species in Northeast China. The methodological framework employed, particularly the integration of population-level analyses with type specimen examinations, provides a valuable model for resolving complex taxonomic issues in Salix and other challenging plant groups.