This article is not an academic paper, but I hope to understand marine life and seafood with a rigorous academic attitude.
The previous article has a preliminary understanding of cephalopods and the latest classification of the eight-wrist general order, and this one continues to explore the general order of the ten wrists.
All members of the Ten Wrists are academically commonly known as squid, and in daily life, they are called cuttlefish, squid, and flower branches in different shapes. Squid is the largest of all cephalopod catches, with more than 90% in every coastal country, making it the most common cephalopod seafood on the market.
Proportion of squid (FAO data, picture adapted from Chen Xinjun)
However, before starting to discuss the ten wrists in detail, I will first add the place that the previous eight wrists are not detailed, that is, the various octopuses commonly found along the coast of China! It is hoped that the common cockles in the market can be distinguished at a glance and calmly with specific reference pictures; however, it should be noted that the most accurate distinction is still molecular genetic markers, of course, you can also look at the only hard parts - the tooth tongue radula and the jaw flak.
The tooth tongue is a unique structure of mollusks, composed of multiple rows of tooth plates, shaped like a file, and can generally only be observed through a microscope! The number and position of the central and lateral tooth tips, as well as the arrangement in the central dentition, are important classification bases; the jaw pieces are the pieces that make up the mouthpiece and are used to bite into food.
The main structure of the octopus, self-compiled
Due to the limited space and the fact that there are not many common types of octopus in the market, here are just three:
True slug/Octopus vulgaris, also known as common octopus, commonly known as octopus, is a common species in the world, mainly distributed in China south of the waters of Zhejiang. The body length can reach 1 meter, the carcass length is generally about 25 cm, and the surface of the body is densely warts; the central teeth are usually repeatedly staggered between 2 3-toothed cusp and 2 5-tooth cusp. The habitats are mostly offshore rocks and algae fields.
Octopus, self-compiled
Octopus variabilis, commonly known in the north as the long eight-banded fish, are widely distributed in the sea areas of northern and southern China, but are more commonly found in the northern coastal waters. Individuals are larger, often pale yellowish brown, darkening in color when disturbed, and also have 5 cusps, but the 2 lateral cusps on either side of the central cusp are up or down between the adjacent central teeth. The meat is thick and edible, accounting for more than 90% of the total.
Long eight striped fish, pictured by self-editing
Amphioctopus fangsiao (formerly known as Octopus ocellatus), commonly known in the north as the eight-striped fish, is also commonly found in northern waters. The body is small and short, the life cycle is also short, the swimming ability is weak, and there is a hidden habit of drilling sand; the 5-tooth pointed central teeth are adjacent to 1 and 2 3-tooth pointed central teeth, respectively. The meat is delicious and is one of the important seafood products in the north.
Eight striped fish, pictured by self-editing
<h1 class = "pgc-h-arrow-right" > the general order of the third and tenth wrists</h1>
Decapodiformes, also known as squid, is known in English as Squid.
Squid can be translated not only as squid, but also often translated as squid! However, in Chinese meaning, squid often refers to one of the ten-wristed order, so it is easy to misinterpret the squid; in addition, the squid has an order, family, and genus definition in classification, and the squid order is called cuttlefish in English, and in Chinese context, the squid can also refer to a common type of cephalopod seafood, which is more likely to cause confusion.
To correctly distinguish between squid and squid, first of all, to understand the academic definition, and then to understand according to the corresponding understanding of different languages, you can see the fire.
Taiwan Province distinguished squid illustration, adapted from Taiwan Good Farmer
The use of the black head indicates that this type of cephalopod is also characterized by inkjet; however, compared with the octopus that also can spray ink, the squid is longer, the eyes are larger, and have an inner shell; in addition, although the squid has ten wrists, its fourth pair has been specialized as a tentacle with suction cups, and this pair of long tentacles is usually stored between the 3rd and 4th wrists, and it will shoot out quickly when catching prey, which is extremely contractile.
Squid structure, figure self-edited
In the past, the ten-wrist general order was usually divided into several categories, such as spinosaurida/Spirulida, ear squid/Sepiolida, squid/Sepiida, tube squid/Teuthida, etc., of which pipe squid were divided into open-eye suborders and closed-eye suborders, but recent studies on germinogenesis have shown that the open-eye suborder and the closed-eye suborder are not the evolutionary branches of the pipe squid, and WoRMS even no longer follows the pipe squid, and instead elevates the two suborders to orders, directly replacing the former.
According to the WoRMS classification, today's decapitated headings contain the following categories:
Bathyteuthida (9)
Microfinida/Idiosepida(7)
Closed Eyes/Myopsida(48)
Oegopsida (252)
Squid order/Sepiida (198)
Spirulida (1)
The latest classification of the ten wrists, the figure is self-compiled
Among these six orders, the spiny squid, microfin, and deep-sea order are usually relatively rare, the species are not many, and the catch value is not large, for example, the spiny squid currently has only one kind - the glowing curly shell squid / Spirula spirula living in the deep sea, the body length is only about 4 cm; in addition to the glow, this deep sea squid also has a unique horn inner shell.
The inner shell of the horn floats from the deep sea and can sometimes be picked up on the seashore.
Curly shell squid, self-edited
There are currently 7 species of microfins, characterized by the tinyness of the flesh fin, common such as pygmy squid/Idiosepius pygmaeus, which is smaller than the curly-shelled squid, and the adult body length is not even 2 centimeters, so that some people call it the smallest squid! However, unlike the curly-shelled squid, the microfin squid mainly inhabits the offshore and does not emit light.
Pygmy squid, self-edited
There are currently 9 species of deep-sea squid, which generally live 700-2000 meters below sea level, of which the deep-sea squid /Bathyteuthis abyssicola is more familiar; the deep-sea squid is also called deep-sea squid, its carcass length is usually less than 8 cm, this squid is not only small, brachiopods are also short, there are not many suction cups on the brachiopods, each brachiopod has only about 100 suckers.
Deep Sea Squid, self-edited
In addition to these rare squid, more into people's vision are the closed-eye, open-eye and squid of the order Squid, which are also the main fishing objects of humans.
Squid order / Sepiida, also known as cuttlefish order, commonly known as cuttlefish or squid, also known as flower branches in the Minnan language region, called cuttlefish in English. The main classifications are (116), (8) and (74) three families, of which the squid family accounts for the largest proportion and is the most common, and is divided into 3 genera.
The main classification of squid order, the figure is self-compiled
Ear squid is an important feature of flesh fins such as ears, this family is not a small family, it has 20 genera and 74 species, which is also a large unit in the cephalopod kingdom; however, this family is relatively small, the production is not much, although there are some places that are often caught, so that it is called cuttlefish, but it is generally not valued.
Two common ear squid, the picture is self-compiled
The hind ear squid (Taiwanese called pseudo-ear squid), this family has only identified 8 species, of which the striped pajama squid (scientific name Sepioloidea lineolata) is the most famous, about 8 cm long, very cute appearance, but is a rare mollusk with tetrodotoxin.
Striped pajama squid, pictured by himself
According to the latest Classification of WoRMS, the Squid family is divided into three genera: Squid/Metasepia(2), Squid/Sepia(107), and Needleless Squid Sepiella(7). Among them, there are two kinds of flower squid, namely flame squid / Metasepia pfefferi and cherry blossom squid / Metasepia tullbergi; flame squid, also known as flame flower branches, is a poisonous squid, its toxicity is even comparable to that of blue circle octopus, the body length is generally not more than 6 cm.
Two kinds of flower squid, pictured by self-editing
Needleless squid/Sepiella is characterized by the absence of bone needles at the back end of the inner shell, and there are 7 species in this genus, of which the needleless squid/Sepiella inermis and the Japanese needleless squid/Sepiella japonica are the most important fishery resources. Man's needleless squid, the traditional cuttlefish, was almost extinct in the 1980s and 1990s due to large-scale fishing, and has recently gradually recovered and been successfully farmed.
Needleless squid, self-compiled
The next article will continue to sort out the squid and gun squid.
(It's not easy to sort out and correct, I hope you can... I can... You know! ）