Merten's butterflyfish

The Merten's butterflyfish (Chaetodon mertensii) is characterized by its primarily yellow body, with a broad black vertical band running through the eye and another at the rear, plus a white area near the dorsal fin. This species is native to the Indo-Pacific region. It has a distinct look marked by its elongated dorsal and anal fins. While recognizable, it's not among the most popular in the aquarium hobby, partly due to its specific care requirements and size, which can reach up to about 18 cm (7 inches) in length.