This study aimed to estimate the parameters of length‐weight relationship for 16 freshwater fish species that inhabit the Aracá and Demeni Rivers, which are two tributaries of the Negro River (Amazonas state, Brazil). The fishes were sampled using gillnets (15 × 2 m, mesh size 30–120 mm between opposite knots), during 6 days each year, in April 2016, November 2018 and April 2019. The gillnets were placed in the river twice each day; in the morning (5–9 a.m.) and in the evening (5–9 p.m.), with a standardized time of 4 hr. Measurements were taken for standard length (SL – 0.1 cm precision) and total weight (TW – 0.01 g precision). The parameters a and b of the equation W_T = a.L_T^b were estimated. This study also provides new data on of maximum lengths for six species, namely, Argonectes longiceps, Hemiodus atranalis, Chalceus erythrurus, Astrodoras asterifrons, Trachydoras steindachneri and Acarichthys heckelii.

中文翻译：

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内格罗河流域（巴西亚马孙州）的16种鱼类的长重关系

这项研究旨在估算居住在阿拉卡河和德梅尼河（这是内格罗河的两个支流）（巴西亚马逊州）的16种淡水鱼物种的长度重量关系参数。在每年的6天（2016年4月，2018年11月和2019年4月）中，使用刺网（15×2 m，网眼大小为30-120 mm，对结之间的网眼）对鱼类进行采样。刺网每天放置在河中两次。上午（5-9点）和晚上（5-9点），标准时间为4小时。进行了标准长度（SL – 0.1厘米精度）和总重量（TW – 0.01 g精度）的测量。参数一个和b等式W的_Ť  = 一个.L _Ť ^b被估计。这项研究还提供了最大长度的新数据为六种，即Argonectes longiceps，Hemiodus atranalis，Chalceus erythrurus，Astrodoras asterifrons，Trachydoras瑞鳖和赫氏萎鳃丽鱼。