Are the cells of marine animals and flora equipped with special ion exchange pumps to mitigate the effects of a saline-rich environment?
Or have the cell's membranes adapted through structural changes to counter the osmotic forces?
This 1969 Steensland paper seems to suggest that the membranes of halophiles are stabilized by sodium ions and they rapidly denature at lower-salt conditions (2.2 vs. 4.3 M). The protein composition of the membrane was generally acidic, stabilized by all the Na+.
As far as what the role of the halophile membrane is in sheltering the cell from the high ionic strength solution seems left unsaid.