What are the physical characteristics of rays?

The body surface of the ray is covered with scales, which are formed by the ectoderm and mesoderm in the occurrence. The scales and teeth are homologous structures. The position of the mouth is not at the snout but on the ventral surface, transversely fissured (so it is called transverse); The even-fins are horizontal; The tail fin is crooked. The gill septum is extraordinarily long, extending to the body surface and connecting with **, so that the gill slit opens directly on the body surface.

The heart has conus arterios. The male genital duct borrows the mesorenal duct. A single cloacal pore opens outside the body.

Males have mating apparatus called flipper legs. Oviparous, ovoviviparous or pseudoviviparous, in vivo fertilization, in vitro development or in vivo development. The spawn is small, but the survival rate is high.

The brain is well developed, and it is more advanced than the bony fish. The brain is large in size, and neurosubstances also appear on the top of the brain.

Ray. The most typical feature of the ray, commonly known as the ray, is that the tail is very thick, and other typical characteristics are having a dorsal or caudal fin, no fins on the head and mouth, and no hard stinger on the tail, such as the following three:

A typical ray, you can see that its tail is thick, there is a small tail fin on the tip of the tail, there is nothing strange on the head and mouth, and there are no poisonous hard spines on the tail, this is a fan ray.

It's a ......The atypical ray, although its body is not flat at all, although it looks a bit like a shark, but you can see that there are indeed no gill holes on the side, and its gills are on the abdomen. We can see the ...... of its tailThat's fucking too thick......The caudal and dorsal fins are ......That's too fucking obvious......The head and mouth are also clean, and there are no poisonous hard thorns on ......the tailIt is called a ray and ...... without any problems

This is a ray that looks typical, but is actually very atypical. You can see that its tail is thick, there is a small tail fin on the tip of the tail, there is nothing strange on the head and mouth, and there are no poisonous hard spines on the tail, and it looks very beautiful and docile ......But I'm going to give you a piece of advice, pretty women are generally not easy to mess with, and so are fish, this is an electric ray that will make you doubt the kind of life that kinds.

Catfish is a kind of catfish, and what we call catfish basically refers to catfish, which is mainly distributed in the Huai River, Yangtze River, Minjiang River and other water systems in the east, and is mainly based on the Yangtze River water system. Because its meat is delicate and delicious, it is rich in nutrition, and anchovy and saury are called "three fresh fish of the Yangtze River", and those who sell fish in the Yangtze River also call catfish "fat fish", but the name is different.

For catfish, the body is long, the snout is tapered, the front is more prominent, and the mouth is lower, and it is crescent-shaped. The lips are thicker and the eyes are smaller. There are four pairs of smaller whiskers.

The dorsal and pectoral fins are serrate, the caudal fin is forked, the body color is pink, the dorsal touch is slightly grayish, the abdomen is white, and the fins are grayish-black.

Catfish belong to the bottom carnivorous fish, like to hunt at night, the temperature of survival is about 0 to 38 degrees, below 20 degrees will reduce the amount of feeding, growth becomes slow, so the temperature is higher for Xiaosui to do catfish fishing is more suitable, for the catfish predation habits and we usually do fishing Huang Lading, catfish predatory habits are almost the same, all belong to nocturnal activities foraging fish. But in normal lakes, rivers do not encounter catfish.

1. Morphological characteristics: The endoskeleton of the ray is completely composed of cartilage, and some parts also have a certain hardness after calcification, but it is different from the hard bone tissue formed by ossification. The body surface is covered with scales, which are formed by the ectoderm and mesoderm in occurrence; The scales and teeth are homologous structures.

2. Habits: Juvenile rays feed on animals that live on the bottom of the sea, such as crabs and lobsters. When they grow up, they mainly hunt mollusks such as squid.

When hunting, rays mainly rely on their sense of smell. When lying on the bottom of the sea, the rays use a special closed-mouth breathing method to avoid inhaling sediment as much as possible. As the ray breathes, the water is sucked in through the tubing above the head and finally flows out through the cleft of the gills on the ventral surface.

3. Distribution: It is distributed in most of the world's water areas, from tropical to near-arctic waters, from shallow sea to deep water below, mainly living in the East China Sea and the South China Sea. The Okinawa region of Japan is one of the most important places to visit for rays, and the aquarium there has a dedicated area for people to see up close.

Carangidae amberjack seriola fish.

The figure below is shownYellowtail seriola dumerili, commonly known as Yellowtail, Red Horse Trevally, Red Horsetail.

There is a yellow longitudinal belt that is not stupid on the silver side of Tizhou, which goes straight to the tail peduncle from the back of the eye, and the juvenile fish and the old adult fish are obvious. The snout is obtuse and rounded, and the main maxilla can reach posteriorly just below the center point of the eyeball. The length of the strip in front of the second dorsal fin is approximately equal to the length of the pectoral fin.

The first dorsal fin has 7 hard spines, the second dorsal fin has 1 hard spines and 26 to 21 soft bars; The anal fin has 1 hard spine and 19 to 21 soft bars. The body length can reach 180 cm. <>

Fish occasionally appear in coastal waters and estuaries where the water quality is clearer, but do not invade freshwater or salty waters with low salinity. Fish is the main food source. Delicious premium table fish. Fresh fish is best for sashimi. The fish head soup is quite delicious.

Fish is also known as rice fish and sensitive fish.

Totoaba Sciaenidae is a fish of the genus Miichthys.

The picture below shows the miichthys miiuy, commonly known as the black fish, the sensitive fish, the perch, the micha liquid fish, and the hairy fish.

<> body color is dark, grayish-brown with purplish-green tinge, and the abdomen is grayish-white and curved. It prefers to inhabit waters with high turbidity. It can make a sound with a swim bladder, and the sex shed is sullen and fierce.

It is distributed in the coastal areas of North Korea and China, and is a warm and temperate pelagic fish in the coastal waters. It usually inhabits muddy or sedimentary bottom areas at depths of 15-70 meters.

The picture below shows miichthys miiuy, commonly known as rice fish, catfish, sensitive fish, hairy fish, and eel.

<> resembles a sea bass, but the flesh is slightly rough, the body color is dark, grayish-brown with a purplish-green tinge, and the belly is grayish-white. The upper edge of the dorsal fin spines is black, and the fin strips ** have a longitudinal black stripe. There is a sunny spot above the axillary part of the pectoral fin.

The rest of the fins are grayish-black. The body shape of the rice fish is flattened and elongated backwards on both sides, and the back and abdomen are shallow arcs.

Dace has a flattened and long body, spindle-shaped, round and blunt snout, similar to carp, but relatively slender, and the forehead is short and thick, the body color is blue-white, the abdomen is blue-gray, the end is reddish-brown, and there are several black patches at the base of the pectoral fin, and the dace is a warm-water fish, the optimal growth temperature is between 15-30 degrees, and the temperature is lower than 7 degrees Celsius and grows slowly.

The body shape of the dace is spindle-shaped, the side is flattened and long, the snout is round and blunt, similar to the appearance of the carp, or lead silver but the shirt is slender, and the forehead of the dace is short and thick, the body color is blue-white, shiny, the belly color is blue-gray, the end is maroon-red radical, and there are several black scales at the base of the pectoral fin on the side of the body.

Dace is a warm-water fish, suitable for growing in a high water temperature environment, the most suitable growth temperature is between 15-30 degrees, not tolerant to low temperatures, slow growth when the temperature is lower than 7 degrees, and the diet of dace is more mixed, mainly feeding on diatoms, green algae, plant detritus, bottom rotting plants, copepods, and cladopods.

When breeding dace to build an area of 5 acres of pond, and to the bottom of the 20 centimeters after the silt, inject meters of deep water, and then put the fry in the pond, during the breeding period for the dace to feed soybean milk, vegetable cakes and other feed, and fry put 1 week later, to regularly inject clean water, bubble disease prevention and control.