Most names refer to hedgehog, but I attribute that to hedgehogs being better known in Europe than porcupines and better pun potential with the words for hedgehog, though in many languages the names for the creatures are interchangeable. English shows no preference (unless the "pin" is short for "pine") and, contrary to popular belief, neither does Japanese. People claim Harimaron comes from "harinezumi" (hedgehog), which is itself made of the words "needle mouse". Seeing as it ony contains the "hari" part, the word for needle, it doesn't necessarily have anything to do with hedgehogs.
In terms of looks, Chespin definitely checks out for porcupine. Many can stand on their hind legs, he has rodent-like buck teeth, the quills can be stiffened for attacking (admittedly a shared feature) and he has a non-nub tail. He lacks the hedgehog's snout, pointy teeth, and overall looks less like a hedgehog than even Sonic. I'm pretty sure he's supposed to be based primarily on a porcupine, which is cool because porkies are really fun and interesting animals.
