Knowing biodiversity: Fishes from the Guareí River basin, a tributary of the Jurumirim reservoir, Paranapanema River, Brazil

Abstract: The Guareí River is a tributary of the Paranapanema River (Brazil), located in the upper portion of the Jurumirim Reservoir. Fish fauna studies in this watershed began in the 2000s, but they were restricted to a few waterbodies. This work conducted a broad survey of the fish fauna in tributary streams and the main channel of the Guareí River. Sampling occurred between February 2017 and November 2018 at 36 sites and using different collection methods. We captured 2,169 specimens belonging to 50 species, 16 families and 6 orders. The species accumulation curve tended to stabilize but indicated that species richness is underestimated. Almost all species are native (46); only three were non-native (Hyphessobrycon eques, Oreochromis niloticus and Poecilia reticulata) and one was undefined (Gymnotus pantanal). Among the native species, two are unknown to science (Bryconamericus aff. iheringii and Hypostomus sp. n.) and three are migratory (Leporinus friderici, Megaleporinus obtusidens and Pimelodus maculatus). In this paper, we provide images of species collected. Results indicate that the Guareí River basin is a hotspot of fish diversity in the Upper Paranapanema River, stressing the need for adequate management and conservation actions.

摘要：瓜雷伊河（Guareí River）是巴西巴拉那佩内马河（Paranapanema River）的支流，地处朱鲁米里姆水库（Jurumirim Reservoir）上游区段。该流域的鱼类区系研究始于2000年代，但此前仅局限于少数水体。本研究对瓜雷伊河的支流河道与干流的鱼类区系开展了全面调查。采样工作于2017年2月至2018年11月间完成，共设置36个采样点并采用多种采集方法。本次调查共捕获2169尾标本，隶属于6目、16科共50种。物种积累曲线趋于平缓，但表明当前物种丰富度存在低估情况。绝大多数物种为本土物种（共46种），仅3种为外来物种（Hyphessobrycon eques、Oreochromis niloticus及Poecilia reticulata），另有1种分类地位未定（Gymnotus pantanal）。在本土物种中，有2种为科学界尚未正式定名的类群（Bryconamericus aff. iheringii与Hypostomus sp. n.），另有3种为洄游性物种（Leporinus friderici、Megaleporinus obtusidens及Pimelodus maculatus）。本研究附带所采集物种的影像资料。研究结果显示，瓜雷伊河流域是巴拉那佩内马河上游区域的鱼类多样性热点区域，凸显了开展合理管理与保护行动的必要性。