Thinouia is a Neotropical genus of lianas with approximately 12 species and is the only genus in tribe Paullinieae with actinomorphic flowers. During a taxonomic revision of the genus and fieldwork in south-western Amazonia, we found a new species that appears similar to Thinouia trifoliata (ex Allosanthus) because of its racemiform inflorescence. However, before describing the new species, we had to confirm that Allosanthus was congeneric with Thinouia so we could place the new species in the correct genus. The results of the phylogenetic analysis, based on molecular data (trnL intron and ITS sequences), show that Allosanthus should be included in Thinouia. Thus, the new taxon is described here as Thinouia cazumbensissp. nov. The new species is described, illustrated and phylogenetic trees showing relationships within supertribe Paulliniodae and Thinouia and the congeneric Allosanthus are given.

中文翻译：

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亚马逊地区的 Thinouia 新种（Paullinieae、无患子科）及其系统发育位置


Thinouia 是新热带藤本植物属，约有 12 种，是 Paullinieae 族中唯一具有辐射对称花的属。在对亚马逊流域西南部的属进行分类学修订和实地考察期间，我们发现了一种新物种，由于其外消旋状花序，其外观与 Thinouia trifoliata（前 Allosanthus）相似。然而，在描述新物种之前，我们必须确认 Allosanthus 与 Thinouia 是同属的，这样我们才能将新物种归入正确的属。基于分子数据（trnL 内含子和 ITS 序列）的系统发育分析结果表明，Allosanthus 应包含在 Thinouia 中。因此，新的分类单元在这里被描述为 Thinouia cazumbensissp。十一月对新物种进行了描述、图示，并给出了显示超级部落 Paulliniodae 和 Thinouia 以及同属 Allosanthus 之间关系的系统发育树。