Study of octopuses, squid, cuttlefish and other mollusks（B）

All members of the order are known as cuttlefish academically, but in daily life they are known as cuttlefish, squid, and flower branches for different shapes. cuttlefish is the most common cephalopod seafood in the market, accounting for more than 90% of all cephalopod fish catches in every coastal country.

There are not many kinds of common octopus in the market. Three kinds are listed:

Octopus vulgaris is a worldwide common species, mainly distributed in the south of Zhejiang Sea in China. Body length up to 1 meter, equator length is generally about 25 cm, body surface dense warts; The central teeth are usually repeatedly interlaced with 2 3-point and 2 5-point teeth. Habitat for the near sea rock reef, algae field, etc.

Octopus variabilis in northern China, is widely distributed in the north and south of China, but more common in the northern coastal areas. The individual is larger, often a light yellow brown, disturbed when the body color will become darker; It also has five cusps, but the positions of the two lateral cusps on either side of the central cusp rise or fall between adjacent central teeth. The meat is hypertrophic, and the edible part accounts for more than 90% of the total.

Amphioctopus fangsiao (formerly Octopus ocellatus), commonly known to the north as Octopus, is also common in northern waters. The body is small, the wrist is short, the life cycle is short, the swimming ability is weak, and the habit of sand drilling is hidden; There are 1 and 2 3-tip central teeth adjacent to the front and rear of the 5 central teeth. Delicious meat is one of the important seafood in the north.

Decapodiformes, or Squid, also known as Squid.

Squid can also be translated as Squid! But in Chinese, squid usually refers to one of the ten carpal orders, so calling it squid is easy to cause a deviation. Adding to the confusion is the fact that squid are classified as orders, families, and genera (the order is called cuttlefish in English), and in the Chinese context, squid can also refer to a common type of head and foot seafood.

Compared with the inkjet octopus, the squid is longer, with larger eyes and an inner shell. In addition, although the cuttlefish has ten arms, the fourth pair has been specialized into the touch arms with suction cups. This pair of long tentacles are usually kept between the third and fourth arms, and they will be rapidly shot out when catching prey, which is extremely contractive.

The current ten-wrist catalogues include the following categories:

• Bathyteuthida(9)

• Idiosepida(7)

• Myopsida(48) with closed eyes

• Oegopsida(252)

• Sepiida(198)

• Spirulida(1)