(from the article `amphibian`) ...North America.Subclass LissamphibiaTriassic to Recent; worldwide.Superorder GymnophionaJurassic to Recent; pantropical.Order `Jurassic fossil`... Found on http://www.britannica.com/eb/a-z/g/85
Gym`no·phi'o·na (-fī'o*nȧ) noun plural [ New Latin , from Greek gymno`s naked + 'ofio`neos serpentlike.] (Zoology) An order of Amphibia, having a long, annulated, snakelike body. See Ophiomorpha . Found on http://www.encyclo.co.uk/webster/G/70