Tympole

Tympole is a round, tadpole-like Pokémon with a tan, circular face. It has large, oval, black eyes; a wide mouth with down-turned corners; and black eyebrows in the shape of quarter notes. Its spherical body is black with no visible limbs. Instead, it has two black-and-blue ringed cheeks akin to half-spheres on either side of its head. It has a long, blue tail with a fan-like shape and a black spot at its base. Tympole vibrates its cheeks to create a sound too high-pitched for humans and other species of Pokémon to hear. The sounds are used in rhythm to communicate with others of its kind, particularly for warning of danger. They are known to sing in high-pitched voices, which creates graceful ripples on the water's surface. The anime reveals that Tympole swim and attack in groups.