A fish with black spots is called a black spotted dogfish.

Black spotted dogfish (scientific name: Esox reicherti), for the dogfish family. Dogfish is a genus of fish, and this species is a specialty fish of the waters of cold regions in high latitudes.

Generally the body length of about 600 millimeters, weight in 1000-2000 grams, the largest individual weight up to 16 kilograms or more. The body is prolonged, the front of the head is flattened, and the muzzle resembles a duck's beak. The mouth is large, with sharp teeth in the premaxilla, mandible, plow bone, crotch bone and tongue. Scales small. Lateral lines inconspicuous. Dorsal fin posteriorly shifted, opposite the anal fin. Body dorsum bronze colored, abdomen white, with black spots on the sides of the body.

But often with new variations depending on the habitat. It is distributed in the ТугурУда River, Timi River, Boronai River, Lake Bel, Erguna River, Shilekha River, Enen River, and Ingoda River, as well as in the Nen River, Heilongjiang River, Songhua River, Ussuri River, Dalai Lake, Jingpo Lake, Wudalianchi, and Suifen River. The type locality of this species is in the Enen and Ingolda Rivers.

Extended information:

p>Morphological features

Large freshwater fish. Generally around 600 millimeters in length and weighing 1,000-2,000 grams, with the largest individuals weighing up to 16 kilograms or more.

Extended body, the front of the head is flattened, and the muzzle resembles a duck's beak. The mouth is large, with sharp teeth of the premaxilla, mandible, plow bone, crotch bone and tongue. Scales small. Lateral line inconspicuous. Dorsal fin posteriorly shifted, opposite anal fin. Body dorsum bronze, abdomen white, with black spots on the sides of the body.

The black-spotted dogfish has a white belly, a grayish-yellowish-green or greenish-brown dorsum, and many black spots scattered along the side of the body, with occasional black spots on its fins, which is why it is called the black-spotted dogfish in taxonomy. The black-spotted dogfish has an elongated, cylindrical body. The front of the head is flattened and looks much like a duck bill. When the dogfish's slender mouth is broken open, the sharp, conical teeth growing in its upper and lower jaws are clearly recognizable.

Baidu Encyclopedia - Black-spotted Dogfish