Knuckles from Sonic is an echidna, a type of small mammal that comes from the family Tachyglossidae. Echidnas are the only surviving monotremes, an order of egg-laying mammals that are similar to marsupials. Knuckles is a red anthropomorphic echidna with red fur that covers most of his body, a black nose on his peach-colored muzzle, and white gloves with red and yellow cuffs.