Kingdom: Animalia

Phylum: Cnidaria

Class: Scyphozoa

Order: Root saliva Parent order Rhizostomeae

Family: Rhizostomatidae

Genus: Rhopilema

Species: R. esculentum

Population Distribution

Jellyfish are widely distributed in tropical, subtropical and temperate coastal areas. Common jellyfish in China include edible jellyfish with smooth umbrellas and only filaments at the mouth and wrist, or rod-shaped jellyfish with both rods, and There are many small warts and yellow-spotted jellyfish on the umbrella surface. Yellow-spotted jellyfish is mainly distributed along the coasts of Guangdong and Guangxi and is somewhat toxic. True jellyfish are found in the Yellow Sea, East China Sea, and Bohai Sea, and are less toxic. The cyan jellyfish is usually more toxic. There is a famous poisonous jellyfish in Australia - square jellyfish, which mainly lives on the coast of Australia. If a person touches its tentacles, he will die in 30 seconds.

1. Jellyfish

The umbrella diameter is 300-500 mm, the largest individual is 1 meter, and weighs about 40 kilograms. The outer umbrella has a smooth surface and a thick gel layer, and each 1/8 of the umbrella edge has 14 to 20 tongue-shaped edge valves. No tentacles. There are 8 sensillae, located at the ends of the main radial tube and the interradial duct respectively. There are 10 to 20 marginal lobes between every two sensillae. There is a small leaf-shaped marginal valve on each side of the sensory organ, also known as sensory marginal valve. The inner umbrella consists of many concentric rings with the stomach cavity as the center point and arranged in an imbricate shape. The circular muscle is reddish brown, dark brown, golden yellow or milky white. There are no radials. There are four kidney-shaped depressed subgenital points on the radial position between the inner umbrellas. The inside of the points are separated by membranes and are not connected to the outside world. There is a papillary protrusion with a rough surface on the outside of each subgenital point. There are 8 pairs of shoulder plates on the outside of the base 1/2 of the mouth and wrist. The lower end is the mouth disk, and 8 mouth wrists are separated from the mouth disk. The shoulder plate is flat on the side and three-winged on the outside. Each wing has many folds, also called suture folds; there are many finger-like appendages and small suction openings on the folds. There are also many filaments on the wings. The mouth and wrist are also in the shape of three wings. The inner wing is larger, which is the main wing, and the outer wing is smaller, which is the aileron. There are many finger-like and spindle-shaped appendages on the wrinkles of each wing, and there are many small suction mouths and touch points. refer to. There is a thick and long rod-like appendage at the end of the wrist. Each small suction port in the mouth and wrist is trumpet-shaped, connected by the small tube to the carpal tunnel, and the carpal tunnel leads to the gastric cavity. The gastric tube system is well developed, with 16 radiating tubes extending from the central gastric cavity to the inner umbrella. Among them, 4 main radial tubes extend from the gastric column, 4 inter-radial tubes extend from the upper boundary of the gastric membrane, and 8 longitudinal radial tubes extend from the upper boundary of the gastric membrane. The main radial tubes and the intermediate radial tubes are arranged alternately. There is a degenerated ring tube at 1/2 of the inner umbrella. This ring tube is especially obvious in the larval stage and is connected with each radial tube. The main radial tube and the inter-radial tube inside the ring tube have multiple branches connected to form a network tube, and the longitudinal radial tubes are not branched. The 16 spokes on the outside of the ring are all branched and extend toward the edge of the umbrella to form a network-like interconnected structure.

This type of adult is generally milky white, because the well-developed circular muscles have a variety of pigment cells, causing the umbrella to appear reddish-brown, cyan-blue, light yellow and brown. In addition, color differences often occur due to different habitat locations. This species is mainly distributed in the northeastern coast of my country.

2. Yellow-spotted jellyfish

It is very similar to jellyfish. The main difference is: there are many short, sharp and hard warts on the surface of the outer umbrella, and there are yellow-brown spots. Each 1/8 of the umbrella edge has 8 oblong lobes. The rod-like appendages on the mouth and wrist are short and small, and the ends of the appendages are spherical or rod-shaped. The genital process is large and oval in shape, with spike-like protrusions on the base surface.

The diameter of an umbrella is generally 250 to 350 mm. The diameter of an umbrella is mostly hemispherical. The center of the umbrella is thicker and stronger, and the edge of the umbrella is thinner. There are radiating ribs in the inner fossa of the eight sensilla, and there is brown pigment at the end of the balance stick. All 16 spokes extend to the edge of the umbrella. The side branches of each radial tube are connected to each other to form a complex network tube structure. It has 8 orifices, three-winged shape, and many mallet-like appendages with enlarged ends. There are 8 pairs of shoulder plates with many filamentous appendages. There are 4 subgenital points.

The adult body is milky white, with many small yellow spots scattered on the surface of the outer umbrella. This species is a tropical species, mostly distributed along the southern coasts such as Fujian and Guangdong.

3. Club-shaped jellyfish

The individuals are small, with an umbrella diameter of 40 to 100 mm and an umbrella height of 50 mm. The outer umbrella is very smooth and thin.

Each 1/8 of the umbrella edge has 14 to 16 slightly rounded and flat edges. There is no genital process and the shoulder plate is very small. The vertical tube is particularly short. The length of the mouth and wrist is about 35 mm, the base is 3 mm, and the diameter of the wrist disk is 12 mm. The rod-shaped appendages attached to the mouth and wrist are rare, and the terminal rod-shaped appendages are about 10 to 12 mm long. The filamentous appendages are underdeveloped and only attached to the shoulder plate. The annular canal is underdeveloped, the internal annular reticular system is wide and obvious, and the inner contour is roughly parallel to the gastric cavity. The sensory canals are branched or reticular. This species is only distributed in the sea area around Xiamen in my country.

4. Sand jellyfish

It is a large jellyfish with an umbrella diameter of 180 to 980 mm, hemispherical, and the surface of the outer umbrella is densely covered with fine particles. The number of limb valves varies greatly, usually 1/8 fimbriae has 14. 8 sensorium. There are 16 radial tubes, and the terminal branches are connected to each other to form a network. The inner umbrella has well-developed circular muscles. There are 8 orifices and wrists, the base is healed, the free end is spread outwards, the end is bifurcated, the side branches are long, and there are many filamentous appendages on the oriocarpals. 4 separate subgenital points, no genital papillae. When alive, the umbrella is brown and the appendages are dark brown. This species is a cold-water species and is mainly distributed in the southern part of the Yellow Sea and the northern part of the East China Sea in my country.