The Cave Characin is a species of tetra fish who makes her home in deep, dark underground ponds. Living in complete darkness, her eyes are vestigal, with the skin having grown over them, and her scales lack pigmentation. She uses her lateral lines to detect vibrations in the water, swimming close to obstacles to examine them. Her swim bladder is connected to her inner ear, amplifying sounds and allowing her to pick up a greater range and frequency. She lives in schools and eats plants, invertebrates and other fish.