Biology of Artemia persimilis Piccinelli and Prosdocimi, 1968 in a hypersaline lake in a semiarid protected area (Parque Luro Reserve, La Pampa, Argentina)

Abstract

Biology of Artemia persimilis Piccinelli and Prosdocimi, 1968 in a hypersaline lake in a semiarid protected area (Parque Luro Reserve, La Pampa, Argentina) Artemia persimilis is the only species of the genus that is native to South America. Its biology has been studied in lakes in the arid diagonal in Argentina, which are affected by agricultural and livestock activities. The aim was to study biological aspects and their relations with environmental variables in a protected lake under conditions similar to those that existed before the increase in human influence on this area. From October 2014 to September 2015, samples were taken monthly from Este Lake (64° 11' 04'' W, 36° 55' 18'' S), which is in the intangible zone of Parque Luro Provincial Reserve. In situ water temperature, dissolved oxygen, water transparency, and pH were determined, and two quantitative zooplankton samples were taken. The maximum depth varied between 0.9 and 0.33 m, the mean salinity was 262.17 g/L (± 43.87), and Na + and Clpredominated. The water transparency was 0.56 m (± 0.21), and the concentration of phytoplankton chlorophyll-a was 6.19 mg/m 3 (± 8.17). The mean density and biomass of A. persimilis were 209.31 ind./L (± 214.04) and 7535.10 µg/L (± 12 376.57), respectively, which exceeded those recorded in other lakes in the region. Nauplii and metanauplii were registered in every month except December and July, and they showed high percentages of total density. A correlation was found between density and temperature but not between density and salinity, which could indicate that the range in Este Lake is optimal for the species. Although it is difficult to prevent colonization by exotic anostracan species by zoochory, the existence of an abundant population of A. persimilis in a protected lake in the central Argentinean region is an optimal opportunity for the conservation of this species.

Corta meromixis en un lago somero de la región semiárida pampeana

“…En la provincia de La Pampa existe abundante información sobre lagos someros de diferente salinidad (Echaniz y Vignatti, 2017. La laguna Parque Luro (Este) está ubicada en una reserva homónima de La Pampa, se comporta como un típico salitral en épocas secas (profundidad de 0,30 m, y salinidad de 350 g/L; Vignatti et al, 2020). Sin embargo, con lluvias extraordinarias ha alcanzado una profundidad de 2,6 m (H. Jacobi, comunicación personal).…”