osmotic or respiratory responses were investigated in larvae (zoeae I and II) and adults of
the freshwater shrimp Macrobrachium amazonicum. 2. 2. In adults, the blood levels of Na+
and Cl− were kept hyperionic in salinities from 0 to 15%. and isoionic (Na+) or slightly
hypoionic (Cl−) in 25%. 3. 3. The blood levels of K+ and Ca 2+ were regulated
hyperionically (and those of Mg 2+ hypoionically) at all salinities tested. 4. 4. Hyperosmotic …