True frogs, the Ranidae, have the widest distribution of any frog family and can be found on most continents except Antarctica.

In general, true frogs have smooth, moist skin with large, powerful legs and webbed feet. Although most are aquatic or semiaquatic, a few are have adapted to life in the trees while others are excellent at burrowing into the ground to seek moisture. True frogs differ greatly in size, from the small wood frog (Rana sylvatica) at an average of 7.88g to the biggest frog in the world, the goliath frog (Conraua goliath) weighing up to three kilograms.

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