Spiny (hedgehog)

From the Super Mario Wiki

Spinies are a species of hedgehogs found in Mario Kart 64. They appeared in Yoshi Valley. If they hit a racer, his or her kart would spin out. They resemble Porcupo from Super Mario Bros. 2 except they're black (notice Porcupos were originally Black) but could still be sub-species. They're in the middle of several paths in Yoshi Valley.