From the Super Mario Wiki
The Beetle is a large, green beetle in purple racing gear. She seems to be good friends with the Kongs. In Donkey Kong 64, she challenges two of the Kongs to races, rewarding each with a Golden Banana upon her defeat. In Angry Aztec, she challenges Tiny Kong to a race down a large slide, where Tiny must collect at least 50 DK Coins and finish first to win. The Beetle reappears in Crystal Caves to challenge Lanky Kong to a race under the same conditions Tiny was put under while using the OrangStand Sprint.