Assessment of the physiological performance of the invasive oriental shrimp Palaemon macrodactylus from an atypical marine population

• Published in: Journal of experimental zoology. Part A, Ecological and integrative physiology Ecological and integrative physiology, 2024-10, Vol.341 (8), p.885-895
• Main Authors: Maraschi, Anieli, Asaro, Antonela, Bas, Claudia Cristina, Ituarte, Romina Belén
• Format: Article
• Language: English
• Subjects: (V)‐type H+‐ATPase; Acclimation; Acclimatization; Acclimatization - physiology; Animals; Brackish water; Chemical analysis; Freshwater; Hemolymph; Hemolymph - chemistry; Inland water environment; Introduced Species; invasive shrimp; ionic regulation; Laboratory experimentation; Marine crustaceans; Moisture content; Muscles; Na+, K+‐ATPase; Na+/K+-exchanging ATPase; Osmoregulation; Palaemon macrodactylus; Palaemonidae - physiology; Physiology; Population studies; Salinity; Salinity tolerance; Seawater; Seawater - chemistry; Shellfish; Shrimps; Sodium; Water analysis; Water content
• ISSN: 2471-5638; 2471-5646; 2471-5646
• DOI: 10.1002/jez.2843

Since 2000, a well‐established population of the invasive oriental shrimp Palaemon macrodactylus has been present in fully marine conditions in the southwestern Atlantic Ocean (~38° S). To assess the physiological performance of this atypical population restricted to fully marine conditions, we conducted a laboratory experiment in which individuals were transferred from 35 ‰S (local seawater) to 2 ‰S; 5 ‰S; 10 ‰S; 20 ‰S; 50 ‰S and 60‰ for short (6 h), medium (48 h), and long (>504 h) acclimation periods. We measured the time course response of relevant parameters in the shrimp's hemolymph; activity of Na+, K+‐ATPase (NKA), and V‐H+‐ATPase (VHA); and muscle water content. Shrimp showed great osmoregulatory plasticity, being able to survive for long periods between 5 ‰S and 50 ‰S, whereas no individual survived after transfer to either 2 ‰S or 60 ‰S. Shrimp hyper‐regulated hemolymph osmolality at 5 ‰S and 10 ‰S, hypo‐regulated at 35 ‰S and 50 ‰S, and isosmoticity was close to 20 ‰S. Compared to 35 ‰S, prolonged acclimation to 5 ‰S caused a decrease in hemolymph osmolality (~34%) along with sodium and chloride concentrations (~24%); the NKA and VHA activities decreased by ~52% and ~88%, respectively, while muscle water content was tightly regulated. Our results showed that the atypical population of P. macrodactylus studied here lives in a chronic hypo‐osmo‐ion regulatory state and suggest that fully marine conditions contribute to its poor performance at the lower limit of salinity tolerance (