Four new species of Forsteronia are described and illustrated, a distribution map and a key for the species of Forsteronia in Brazil provided, and Forsteronia myriantha lectotypified. Forsteronia manausana resembles F. brevifolia, but differs by its glabrous filaments and smaller leaves. Forstersonia nitida shows affinity to F. tarapotensis but is distinguished by the combination of subcoriaceous, elliptic leaves, large-bracted inflorescences, and somewhat larger flowers.Forsteronia paraensis is apparently most closely related to F. laurifolia but can be separated by its larger and more heavily veined leaves, longer and more floriferous inflorescences, and pubescent ovaries. Forsteronia prancei is morphologically similar to F. manausana, from which it is distinguished by the larger and more coriaceous leaves, denser and more hemispheric inflorescence, and larger flowers.

中文翻译：

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Forsteronia (夹竹桃科, Mesechiteae) 的新种和新的选型分类

描述和说明了四种新的 Forsteronia 物种，提供了巴西 Forsteronia 物种的分布图和密钥，并提供了 Forsteronia myriantha 的选型。Forsteronia manausana 类似于 F. brevifolia，但不同之处在于其无毛的细丝和较小的叶子。Forstersonia nitida 表现出对 F. tarapotensis 的亲和力，但其特点是结合了皮下、椭圆形的叶子、大苞片花序和稍大的花。 Forsteronia paraensis 显然与 F. laurifolia 的亲缘关系最密切，但可以通过其更大和更多来区分叶脉浓密，花序更长，花序更多，子房被短柔毛。Forsteronia prancei 在形态上与 F. manausana 相似，区别在于它的叶子更大更皮质，