Cairns Aquarium has, supposedly, the 'only freshwater sawfish in captivity in the world'. It's signed on the tank as Pristis pristis (or Pristis microdon, I can't remember. Both names are synonyms anyway). Is there any difference between the freshwater sawfish and the largetooth sawfish, the same species, also Pristis pristis? Are they separate populations of the same species, one living in freshwater and the other marine? Can any largetooth sawfish be kept in freshwater, and any freshwater sawfish be kept in saltwater (given they were properly acclimated)? If so, does that make the 'only freshwater sawfish in captivity in the world' technically untrue, as others of the species are kept (but in marine tanks)?
