Bryconops cyrtogaster, a poorly-known species endemic from the Oyapock River at the border between French Guyana and Brazil, is redescribed herein based on examination of available type material, as well as newly collected material. Additionally, a new rheophilic species from the rio Jari rapids, lower Amazon basin, Brazil, is described. The two species belong to the subgenus Creatochanes, and are unique among the congeneres for possessing a posteriorly positioned humeral blotch, at the level of the sixth and seventh lateral line scales. They differ from each other by meristic and morphometric characters. The list of endemic species in the rio Jari basin is revised. This article is protected by copyright. All rights reserved.

中文翻译：

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Bryconops cyrtogaster (Norman) 的真实身份，以及对来自亚马逊河下游 Rio Jari 的 Bryconops Kner (Characiformes: Iguanodectidae) 新物种的描述

Bryconops cyrtogaster 是法属圭亚那和巴西边界的奥亚波克河特有的鲜为人知的物种，本文根据对可用类型材料和新收集材料的检查重新描述。此外，还描述了来自巴西亚马孙河流域下游的 rio Jari 急流的一种新的亲流性物种。这两个物种属于 Creatochanes 亚属，在同类物种中是独一无二的，因为在第六和第七侧线鳞片的水平上具有位于后部的肱骨斑点。它们在分生和形态特征上彼此不同。里约贾里盆地特有物种清单已修订。本文受版权保护。版权所有。