Abstract

Detecting a potentially invasive introduced species is crucial for efficient conservation strategies. We recorded the first occurrences of the “pirambeba” Serrasalmus geryi in the upper Paraná River floodplain, Brazil, in December 2019. A long-term ecological research program (PELD site 6) has been monitoring the region since 1986. One specimen was collected in the Itaipu Reservoir (106.2 mm standard length (SL)) and two other in the Ivinhema River, a tributary of Paraná River (167.1–183.0 mm SL). Previous studies have reported an agonistic interaction between two syntopic congeners in the upper Paraná River floodplain, namely S. maculatus (native) and S. marginatus (invasive), with resulting decrease in the abundance of the native species. Here, we warn that the introduction of S. geryi may act in synergism, aggravating this trend, although little is known about the behavior of S. geryi.

中文翻译：

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新的潜在侵略者：巴西巴拉那河上游平原上的Pirambeba Serrasalmus geryi（Characiformes：Serrasalmidae）的第一记录

摘要

发现潜在的入侵物种对于有效的保护策略至关重要。我们于2019年12月记录了巴西巴拉那河上游平原上首次出现的“ pirambeba” Serrasalmus geryi。自1986年以来，一直在对该地区进行长期的生态研究计划（PELD站点6）。伊泰普水库（106.2毫米标准长度（SL））以及另外两个在伊拉娜河（巴拉那河的支流）（167.1–183.0毫米SL）中。先前的研究报道了巴拉那河上游平原的两个同系同类物之间的激动性相互作用，即S. maculatus（原生）和S.marginatus（入侵），导致本地物种数量减少。在这里，我们警告说，虽然对S. geryi的行为知之甚少，但引入S. geryi可能会产生协同作用，加剧了这一趋势。