Effects of temperature and salinity on prereproductive life span and reproductive traits of two species of Artemia (Branchiopoda, Anostraca) from Argentina: Artemia franciscana and A. persimilis

摘要

The identification of the environmental conditions inducing different ecophysiological responses in the different strains and populations of the brine shrimp iArtemia should improve the understanding of their biogeographic distribution. Nauplii from two Argentinean brine shrimp populations, iArtemia persimilis from Salinas Grandes de Hidalgo (province of La Pampa) and iArtemia franciscana from Laguna Mar Chiquita (province of Cordoba), were grown up until adulthood at different salinities (30, 60, 90, 120 gLu-1) and temperatures (12, 21, 28^'C). The aim was to assess the effects of these different conditions on prereproductive life span and reproductive traits. Results evidenced that at 21 and 28^'C, at any salinity, iA. franciscana from Laguna Mar Chiquita attained higher survival and fecundity, after a shorter prereproductive period, than iA. persimilis from Salinas Grandes de Hidalgo. These data support that iA. franciscana, considered a superspecies, exhibits higher phenotypic plasticity than iA. persimilis, and that iA. persimilis is better adapted to lower temperatures than iA. franciscana. These differences in temperature and salinity tolerance could explain the present distribution of these two species in the South Cone in South America.