叶下珠科三脉守宫木在中国的分布考证

Distribution clarification of Breynia trinervia (Phyllanthaceae)in China

关键词:  黑面神属, 守宫木属, 叶下珠族, 云南, 错误鉴定

Key words:   Breynia, Sauropus trinervius, tribe Phyllantheae, Yunnan, misidentification

摘要:

为明确三脉守宫木(Breynia trinervia)在中国的分布状况,该研究采用经典形态地理学方法,对早期文献记载的该物种凭证标本及相关馆藏标本进行了形态对比与分类核查。结果表明:(1)文献记载该物种分布于中国云南会泽县和开远市等地的凭证标本实际为鼠李科(Rhamnaceae)植物毛蛇藤(Colubrina javanica),说明此前三脉守宫木的中国分布记录源于标本鉴定错误。(2)进一步标本研究发现,来自云南盈江县的一号标本,其形态特征(卵状披针形叶片、基出三脉、星状雄花花萼)与三脉守宫木的模式标本一致,证明其在中国确有分布。(3)结合标本观察及文献资料,给出了该物种的中英文形态描述,并讨论了其地理分布的生物地理学意义。该文纠正了三脉守宫木早期分布记录的错误,首次确认其在中国云南盈江县的自然分布,为中国黑面神属物种分类学研究提供了关键依据,同时为云南盈江县作为古热带与东亚植物区系过渡带的生物地理学地位提供了佐证。

Abstract:

To clarify the distribution status of Breynia trinervia(Phyllanthaceae)in China, this study employed traditional morphogeographical methods to examine voucher specimens cited in early literature and related herbarium collections. The results were as follows:(1)The specimens cited in literature for the previously reported distribution of this species in Huize County and Kaiyuan City, Yunnan, China, were actually Colubrina javanica(Rhamnaceae), indicating, the previous distribution records of B. trinervia in these areas resulted from specimen misidentification.(2)Further examination revealed a specimen collected from Yingjiang County, Yunnan, whose diagnostic morphological characters(ovate-lanceolate leaves, three basal veins, and star-shaped calyx in male flowers)are consistent with the type specimen of B. trinervia, confirming its natural distribution in China.(3)Based on specimen observations and literature review, this study provides detailed morphological descriptions of B. trinervia in both Chinese and English, and discusses the biogeographical implications of its distribution. In conclusion, this work corrects the previous errors in the distribution records of B. trinervia, confirms the natural distribution of B. trinervia in Yingjiang County, Yunnan, China, provides a evidence for the taxonomic research of species in the genus Breynia in China, and substantiates the biogeographical importance of Yingjiang County, Yunnan Province, as a transition zone between the Paleotropical and East Asian floras.