Abstract—

The results of the study of the distribution and biology of the duskyfin glassy perchlet Parambassis wolffii (Bleeker, 1850) in the Mekong Delta in 2019–2020 are presented. It is established that the species reaches the highest abundance and biomass in the freshwater part of the delta. The water temperature at which individuals of the species were encountered was 27.8–34.1°C, salinity, up to 1.51‰, depths, from 2 to 35 m. The maximum total length of females and males was 20.0 and 14.7 cm, respectively, and the maximum age was 6 years. The parameters of the von Bertalanffy equation are as follows: the maximum length is 17.2 cm, the growth rate constant is 0.18, t₀ = −2.35. The value of the coefficient b in the equation on the weight-length relationship is 3.002 ± 0.056 for females (isometry) and 2.774 ± 0.064 for males (negative allometry). Intersexual differences by the in Fulton’ condition factor were established: in females 3.71 ± 0.04, in males 3.53 ± 0.03. The first mature individuals were found at a length of 7–8 cm at the age of 1+.

中文翻译：

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越南湄公河三角洲暗色鲈鱼Parambassis Wolffii（Ambassidae）的分布和生物学

摘要——

介绍了 2019-2020 年湄公河三角洲暗色玻璃鲈鱼Parambassis Wolffii (Bleeker, 1850)的分布和生物学研究结果。已确定该物种在三角洲淡水部分达到最高丰度和生物量。该物种个体遇到的水温为27.8–34.1°C，盐度高达1.51‰，深度为2至35 m。雌性和雄性的最大总长度分别为20.0和14.7厘米，最大年龄为6岁。von Bertalanffy方程的参数如下：最大长度为17.2cm，生长速率常数为0.18，t ₀ = -2.35。体重-身长关系方程中的系数b值对于女性（等长）为 3.002 ± 0.056，对于男性（负异速）为 2.774 ± 0.064。确定了富尔顿状况因素的两性差异：女性为 3.71 ± 0.04，男性为 3.53 ± 0.03。第一个成熟个体在 1 岁以上时体长为 7-8 厘米。