Shouldn't Psyduck be named as Golduck and Golduck named Psyduck ?
Golduck's name origin:
Golduck may be a combination of gold and duck. While Golduck itself is not colored gold, gold is often used in the Pokémon canon to symbolize the Psychic type: the Gold Gummi is the Gummi variety loved by Psychic-type Pokémon, and the Marsh Badge's Japanese name is "Gold Badge".
That pretty much explains it...
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