Demographics and reproductive characteristics of Pseudetroplus maculatus (Bloch, 1795) in Cochin Estuary situated on the South-west coast of India were studied during June 2015 to May 2016. A total of 710 individuals (male = 392 and female = 318) were collected from the Cochin Estuary having TL and BW ranging from 43.2–93.2 mm and 1.45–13.64 g respectively were used for the study. The von Bertalanffy growth curve showed the growth coefficient (K) and growth performance index (ø) were 0.700/year and 3.796 respectively. Natural mortality (M = 1.24/year) of P. maculatus was higher than fishing mortality (F = 0.12/year), and present level of exploitation (E = 0.10) was less than 60% of the predicted maximum exploitation, which indicates that the stock is sustainable under current fishing strategy. There were two recruitment periods per year. Males were predominant in the catches and the overall sex ratio was 1.00:0.81, which significantly deviated from theoretical 1:1 distribution with 55.20% males and 44.80% females. The pattern of gonadosomatic index (GSI) and proportion of mature individuals suggest two peaks in the spawning season of P. maculatus occurred during May to July and October to December. The length at 50% maturity (L₅₀) for males and females was estimated at 71.00 mm TL and 69.96 mm TL respectively. The absolute fecundity estimates vary between 508 and 830 eggs with an average of 683 and the relative fecundity fluctuated between 69.17 and 108.78 eggs/gram with an average of 89.21. The biological information on growth, mortality, exploitation, spawning season, length at first maturity and fecundity provided in this study will be useful for developing sustainable management practices to conserve this poorly known cichlid species.

2015 年 6 月至 2016 年 5 月期间，研究了位于印度西南海岸科钦河口的Pseudetroplus maculatus (Bloch, 1795) 的人口统计学和繁殖特征。共收集了 710 只个体（男性 = 392 和女性 = 318）。研究使用了 TL 和 BW 范围分别为 43.2-93.2 毫米和 1.45-13.64 克的 Cochin Estuary。von Bertalanffy 增长曲线显示增长系数（K）和增长绩效指数（ø）分别为0.700/年和3.796。P. maculatus的自然死亡率（M  =1.24/年）高于捕捞死亡率（F  =0.12/年），目前的开发水平（E = 0.10) 小于预测最大开发量的 60%，这表明在当前的捕捞策略下该种群是可持续的。每年有两次招聘期。捕捞中以雄性为主，总体性别比为 1.00:0.81，明显偏离理论 1:1 分布，雄性占 55.20%，雌性占 44.80%。性腺体指数（GSI）的模式和成熟个体的比例表明P. maculatus产卵季节的两个高峰发生在5-7月和10- 12月。雄性和雌性50% 成熟时的长度 ( L ₅₀ ) 估计为 71.00 毫米TL和 69.96 毫米TL分别。绝对繁殖力估计值在 508 至 830 个鸡蛋之间变化，平均为 683 个，相对繁殖力在 69.17 至 108.78 个鸡蛋/克之间波动，平均为 89.21。本研究中提供的关于生长、死亡率、开发、产卵季节、初熟长度和繁殖力的生物学信息将有助于制定可持续管理实践，以保护这种鲜为人知的慈鲷物种。