Fish Freak, are you sure you don't have the small freshwater species Rhinogobius duospilus? It only grows 2 inches long. Males look very different from females during breeding.
Tom500, how long is "their whole lives"? Of course it's going to live its whole life in freshwater if freshwater is what kills it.
Tom500, how long is "their whole lives"? Of course it's going to live its whole life in freshwater if freshwater is what kills it.