Here we describe and illustrate two new species of angraecoid orchids from East Africa, Tridactyle delepierrei and Ypsilopus iversenii, respectively from Albertine Rift (Rwanda and Uganda) and west Usambaras (Tanzania). The first species is closely allied to the three species of Tridactyle sect. Eggelingiae and to Tridactyle nalaensis. The second species is closely related to Y. leedalii from the southern highlands of Tanzania, and the affinities of these two species to other Ypsilopus are discussed. Diagnostic and morphological characteristics of these new species along with identification keys are provided, including those for the species of Tridactyle from East Africa and the Albertine Rift, and for the species of Ypsilopus sect. Ypsilopus. These new species are threatened with extinction based on the categories of the IUCN Red List, with T. delepierrei suggested to be Endangered (EN B1), while Y. iversenii would be Critically Endangered (CR). Our findings highlight the need for further orchidological inventories and taxonomical studies to support evidence-based conservation and management of the remaining montane forests of East Africa.

中文翻译：

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东非类（兰科，Angraecinae）的新奇

在这里，我们描述和说明了来自东非的两种新种兰花，Tridactyle delepierrei和Ypsilopus iversenii，分别来自 Albertine Rift（卢旺达和乌干达）和西 Usambaras（坦桑尼亚）。第一个物种与Tridactyle教派的三个物种密切相关。Eggelingiae和Tridactyle nalaensis。第二个物种与来自坦桑尼亚南部高地的Y. leedalii密切相关，并讨论了这两个物种与其他Ypsilopus 的亲缘关系。提供了这些新物种的诊断和形态特征以及识别密钥，包括Tridactyle来自东非和阿尔贝蒂裂谷，以及Ypsilopus教派的物种。伊西洛普斯。根据 IUCN 红色名录的类别，这些新物种面临灭绝威胁，建议T. delepierrei为濒危（EN B1），而Y. iversenii为极危（CR）。我们的研究结果强调需要进一步的兰花学清单和分类学研究，以支持东非剩余山地森林的循证保护和管理。