Bicolor Blenny(Ecsenius bicolor)
The Bicolor Blenny (Ecsenius bicolor) is a popular saltwater fish known for its unique color transition. It typically features a dark (blue, brown, or black) anterior (front) half and a lighter posterior (rear) half, which can be yellow, orange, or reddish. They are relatively small, reaching about 4 inches (10 cm) in length, and are commonly found in the Indo-Pacific region.