What I know as the Summer Flounder (Paralichthys dentatus) is what Bill is discussing (I Think) and also goes by the common name of fluke. The range of this fish tends to me more northern than the Southern Flounder (Paralichthys lethostigma). Their ranges overlap but the numbers are low here in my area. They are very similar and ID can be tricky. I have investigated briefly and it is clear they have a wide range of salinity tolerance but I am not sure about zero salinity. I would think due the range being more northerly they would have be more cold tolerant but I am not sure. Someone up on the northern half of the east coast should try it out.

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