Paper Title
Extraordinary Properties of Artemia spp. Under Laboratory Conditions

Abstract
Artemia spp. as a model organism from Urmia Lake are used in the studies on life history and strategies during hypersalinity conditions. Urmia Lake is in drought crisis, and currently water salinity in this lake increased to 300 gL-1. In the present study, effects of acending salinity especially hypersaline treatments on survival and growth in three Artemia species namely: (Artemia urmiana, Artemia franciscana and parthenogenetic Artemia) were considered. Six salinity concentrations (50, 80, 150, 200, 250 and 300 gL-1) were applied in this experiment. Survival rate showed that in culture period, survivals were decreased gradually, but in hypersaline treatments (200, 250, 300 gL-1), we were observed dramatic decline in survival parameter. In addition, the mortality rate was calculated for three populations. We were observed high mortality between all salinity treatments in day 8 perhaps as a result of larvae phase, but the mortality rate became low until senescent phase, in senescent phase as a final phase. We were expected again high mortality. Growth in three species over time was gradually increased to a constant level, but for each salinity and each population, time to reach a constant level were different. In addition, in hypersaline media (200, 250, 300 gL-1), early maturity were observed for three species. Keywords - Artemia spp. Ascending Salinity, Survival, Mortality, Growth, Urmia Lake, Iran