I went to Japan due to a school trip, and I stayed with a host family for 1 week. And I asked so do you guys have japanese fighting fish, they had a bewildered look on their face. Than we googled it on their computer, and it says they are from thailand, yet people call them japanese fighting fish.
Misconception or mislabeled? This is exactly how people still calling SUSHI Raw fish, which in fact SUSHI is not raw fish but SASHIMI is.
Even googling Japanese fighting fish shows links and images:
http://www.misinformer.com/archive/2000/08/28/
http://www.petsmo.com/idealbb/view1494.html
http://www.petsmo.com/pets/pet103.html