please check out this article. too bad they dont mention whether they are in completely fresh water or brackish. does anyone live close by to that area?
http://uk.news.yahoo.com/rare-seaho...M0BHBzdGNhdAN3b3JsZARwdANzdG9yeXBhZ2U-;_ylv=3
http://uk.news.yahoo.com/rare-seaho...M0BHBzdGNhdAN3b3JsZARwdANzdG9yeXBhZ2U-;_ylv=3