Ranidae? The gobiidae? The goby? Luciogobius？ Marine fish (I don't know what kind)

What is the picture below? Luciogobius, a flat-headed tiger fish? Platypus?

What is the picture below? Spotted piranha.

The body is slender and rod-shaped, with a slightly cylindrical front and a flat back. The head is flat, long and wide, with protruding cheeks and sunken back; Small eyes, covered with skin, no free eyelids. Big mouth, oblique fissure, mandibular protrusion. The tongue is very wide, with a deep notch at the front end and a fork shape. The teeth are small and sharp, with multiple rows in each jaw, which are arranged in a narrow band without canine teeth. The body is completely naked and scaleless. The first dorsal fin does not exist; The second dorsal fin is quite low and located at the back of the body. The gluteal fin is roughly opposite to the second dorsal fin. The pectoral fin is quite large and round. The ventral fin is short, and it becomes disc-shaped. The trailing edge of the caudal fin is round. The body is light brown to dark brown, densely covered with tiny black spots. There are large areas of pale round spots on the head, back and sides of the body. The dorsal fin, pectoral fin and caudal fin have small black spots and light round spots, which are arranged in rows or bands. The gluteal fin and ventral fin are pale.