Kawanishi Shiden-Kai

Float planes generally trace their roots to land-based aircraft, not the other way around.  The Shiden-kai, seen magnificently in this 2-for-1 painting by Koike, was a famous exception.  A heavy modification of the Shiden, which was itself just the Kyofu float plane with the float removed, it managed to evolve into the Navy's best fighter of the war despite its unorthodox pedigree.