Finneon

Finneon, known as Keikouo in Japanese, is a Water-type Pokémon introduced in Generation IV. It has an ellipsoid body with a black upper half and a light blue lower half, along with pink stripes on its sides. Its most notable feature is its pair of blue caudal fins that resemble butterfly wings with pink spots. Female Finneon have larger bottom lobes on their tail fins than males. Finneon's pink stripes and spots can absorb sunlight, which allows those areas to shine vividly at night, serving as both camouflage and a way to attract prey. Often called the "Beautifly of the Sea", Finneon lives in schools, sometimes with Lumineon. They swim near the surface during the day to absorb sunlight and dive deeper at night. Due to their beautiful appearance, they are popular with divers and found near resorts that feed them. Finneon evolves into Lumineon at level 31.