Sometimes a peacock gudgeon is referred to as a peacock goby but they are not true gobies. Unlike the fishes of the goby family, peacock gudgeons do not have fused pectoral fins. The typical fused pectoral fins are the trademark of a true goby. So the name peacock goby stands as incorrect and the fish are called peacock gudgeons that belong to the family of Eleotridae. The peacock gudgeons have a blurry black spot at the start of their tail fins. This is visible in every fish irrespective of the sexual dimorphism in males and females. This looks very similar to the black spot present at the same position in peacocks. For this reason, this fish gets the moniker peacock in its name. Also, they have somewhat bluish scales like a peacocks' blue body, accentuating the semblance between the two.