Effect of salinity on reproduction and survival of the copepod Pseudodiaptomus annandalei Sewell, 1919

The effect of salinity on reproduction, lifespan and survival rate, and the tolerance range on salinity shock of Pseudodiaptomus annandalei Sewell, was studied under controlled laboratory conditions. All individuals were fed with Platymonas subcordiformis. The total number of offspring was the most at 15 ppt, secondly was at 10 ppt among seven salinity levels during 10 days. The naupliar survival rate was the highest (98.33%) at 15 ppt when the nauplii were reared until some became adults at four salinity levels (5, 10, 15, 20 ppt respectively). The highest total reproduction (334 ± 171.6 nauplii female− 1 (mean ± S.D.)) and mean daily offspring (22 ± 6.4 nauplii female− 1 day− 1 (mean ± S.D.)) were achieved at 15 ppt over a period of life. The optimum salinity was 15 ppt for the fecundity and the naupliar survival rate, and the appropriate salinity range was 5–20 ppt. The salinity tolerance of female P. annandalei was better than the male through comparison of their survival rate at several salinity shocks and the tolerance range of female and male were 4.5–40.5 ppt and 12.9–38.7 ppt respectively during 48 h.