Pit Plants[1] are a dark green colored variety of Big Piranha Plants with spikes on their faces that live in quicksand pits in the desert. Only one Pit Plant appears, in Mario Kart: Double Dash!! in Dry Dry Desert, where it is located in the quicksand pit waiting for racers to fall in.
Though Dry Dry Desert returns as a retro course in Mario Kart 8 and Mario Kart 8 Deluxe, the Pit Plant is absent as Lakitu pulls the player out of the pit before they fall in.