中国隔距兰属（兰科）一新记录

摘要

Cleisostoma Bl.is an orchid genus with approximately 100 accepted species widely distributed in tropical and subtropical areas.There are about 16 species in China (4 endemic)before.Cleisostoma aspersum (Rchb.f.)Ga-ray,so far known only from Yunnan,is reported from China.A detalled description and photos are provided.This species is easily distinguished from its relatives by bilobulate leaves,fat and obtuse midlobe of the lip,conical rostel-lum with an oblique apex,and beaked operculum.It is similar to Cleisostoma discolor Lindl.in floral morphology, but the latter differs by having a lip with thin spathulate truncate midlobe,with erose front edge.%隔距兰属(Cleisostoma Bl．)是兰科植物中较大的一个属，约有100种，广泛分布于热带、亚热带地区.中国约有16种，其中4种为特有.该文报道了该属一中国新记录———二齿叶隔距兰[Cleisostoma aspersum (Rchb． f．)Garay]，并提供描述和照片，目前该种仅见于云南.与近缘种类相比，本种具有以下鉴别特征：叶齿状二裂；唇瓣中裂片肥厚，前缘钝；蕊喙圆锥状，先端歪斜；药帽喙状等.在花部形态上，该种与 Cleisostoma discolor Lindl．相似，然而后者的唇瓣中裂片明显较薄，匙状方形，并且具有啮齿状边缘，易于区别.