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>Squirtle is a squirrel/turtle hybrid
I'm pretty sure this started out as a troll fact but I've seen it repeated in earnest in recent years. The logic is that the Squirtle line has features in common with squirrels; swirly/fluffy tails, and rodent-like ears. Also, the name Squirtle is meant to be a combo of "squirrel" and "turtle".
But the original japanese name, Zenigame, makes no reference to squirrels, and Squirtle is actually short for 'squirt turtle'.