On a parthenogenetic population of Artemia (Crustacea, Branchiopoda) from Algeria (El-Bahira, Sétif))

Resumo

The brine shrimp Artemia is a small crustacean of hypersaline lakes which is commonely used in larviculture. There are parthenogenetic forms and bisexual species. The formers are from the Old World, and are the most widespread. They are known to prefer high temperatures and relatively stable environments, they are more fertile than sexual species and usually reproduce by ovoviviparity. The parthenogenetic population of Artemia from El-Bahira Lake (10 ha area), situated in the High Plateaus of Northeastern Algeria (1034 m alt), has been characterized and surveyed during two hydroperiods of 2009 and 2013. It has been found to develop only in cold seasons (winter and spring), even if the lake doesn’t dry in summer, and salinities between 46 and 127 ppt. It reproduces by oviparity and produces few cysts (5.69 ± 3.6 and 98.00 ±  28.32 offsprings/brood). Indeed, it behaves more like bisexual Mediterranean populations of A. salina than other parthenogenetic populations. Individual density was much lower during the hydroperiod of 2013, whereas fecundity was higher than in the previous hydroperiod (2009). Cyst reserve was estimated at 133.13 kg of dry weight which corresponds to a rate of 13.31 kg.ha^-1