>>45389360>very short stubby legs>no toes, which are a prominent part of frogs>no snout>no mouth at all>no extendable tongue>no recognizable frog skin patterns>doesn't sing>doesn't jump>doesn't swim with its legsPolitoed has many of these traits, so even someone who has never seen a pokemon before will immediately recognize it as a frog character.
Poliwrath doesn't look like any animal in particular, I can only associate it with tadpoles because it starts as Poliwag.