Effects of salinity-temperature combination on growth and reproduction of the Caspian Amphipod, Pontogammarus maeoticus (Sowinsky, 1894), under laboratory condition

ontogammarus maeoticus is an epibenthic amphipod that is very well adapted to life in estuaries and shallow coastal waters. In the southern coasts of the Caspian Sea, this species is the most abundant macrofaunal species. In the present study, the effect of two important environmental factors, temperature (25 and 30ºC) and salinity (4, 8 and 12ppt), on the life history of adult individuals of P. maeoticus was analyzed in laboratory to assess survival rate, growth and reproductive characters. The results of this study showed that survival rates of adult individuals were similar (P>0.05) among different treatments, despite higher survival rate at 30°C. The growth rate of adult individuals was significantly affected by temperaturesalinity interaction (P<0.05). The growth rate was significantly lower in 25ºC -8 and 12ppt and 30ºC-12ppt compared with the other combinations of temperature-salinity. Adult individuals of P. maeoticus at 25°C required one week more time than those reared at 30°C to complete their sexual maturation period. The relative number of released offspring showed no considerable difference among the different temperature-salinity conditions (P>0.05). In overall, the combination of 30°C and 8ppt can be considered as the optimal temperaturesalinity condition for culture of adult P. maeoticus.