''Coilia nasus'', also known as ungeo and the Japanese grenadier anchovy or Chinese tapertail anchovy is a species of

ray-finned fish Actinopterygii (; ), members of which are known as ray-finned fish or actinopterygians, is a class of bony fish that comprise over 50% of living vertebrate species. They are so called because of their lightly built fins made of webbings of sk ...

from the family

Engraulidae An anchovy is a small, common forage fish of the family Engraulidae. Most species are found in marine waters, but several will enter brackish water, and some in South America are restricted to fresh water. More than 140 species are placed in 1 ...

(anchovies). It grows to

total length Fish measurement is the measuring of individual fish and various parts of their anatomies, for data used in many areas of ichthyology, including taxonomy and fishery biology. Overall length Standard length (SL) is the length of a fish measured f ...

; it is a relatively large species for its genus. It is found in marine, freshwater, and brackish water at depths down to . It is an example of an

anadromous Fish migration is mass relocation by fish from one area or body of water to another. Many types of fish migrate on a regular basis, on time scales ranging from daily to annually or longer, and over distances ranging from a few metres to thousa ...

fish species, with some populations moving to freshwater to spawn. Overall they are distributed in the northwest Pacific, between 21–42°N and 109–134°E, or from

Guangdong ) means "wide" or "vast", and has been associated with the region since the creation of Guang Prefecture in AD 226. The name "''Guang''" ultimately came from Guangxin ( zh, labels=no, first=t, t= , s=广信), an outpost established in Han dynasty ...

in China to the west coast of the

Korean peninsula Korea is a peninsular region in East Asia consisting of the Korean Peninsula, Jeju Island, and smaller islands. Since the end of World War II in 1945, it has been politically divided at or near the 38th parallel between North Korea (Dem ...

and the Ariake Sound in southwestern Japan. A traditional delicacy, the species is commercially fished in Korea, China and Japan. In China it is one of the most expensive fish sold, and as the anadromous variety is more expensive than the freshwater variety, the industry is mostly focussed in the

Yellow Sea The Yellow Sea, also known as the North Sea, is a marginal sea of the Western Pacific Ocean located between mainland China and the Korean Peninsula, and can be considered the northwestern part of the East China Sea. Names It is one of four ...

East China Sea The East China Sea is a marginal sea of the Western Pacific Ocean, located directly offshore from East China. China names the body of water along its eastern coast as "East Sea" (, ) due to direction, the name of "East China Sea" is otherwise ...

, and

Yangtze The Yangtze or Yangzi ( or ) is the longest river in Eurasia and the third-longest in the world. It rises at Jari Hill in the Tanggula Mountains of the Tibetan Plateau and flows including Dam Qu River the longest source of the Yangtze, i ...

. Some Chinese populations migrate anadromously every spring up the

Yangtze River The Yangtze or Yangzi ( or ) is the longest river in Eurasia and the third-longest in the world. It rises at Jari Hill in the Tanggula Mountains of the Tibetan Plateau and flows including Dam Qu River the longest source of the Yangtze, i ...

before their final gonadal maturation in order to spawn in the middle and lower reaches of the

. After this the mature fish then migrate back to the sea. Other groups have been reported to be resident in freshwater lakes during their entire life cycle, making the species an interesting model of partial migration or migratory dimorphism. To understand this process a 870Mb length

reference genome A reference genome (also known as a reference assembly) is a digital nucleic acid sequence database, assembled by scientists as a representative example of the genome, set of genes in one idealized individual organism of a species. As they are a ...

has been assembled, and using this a

population genetics Population genetics is a subfield of genetics that deals with genetic differences within and among populations, and is a part of evolutionary biology. Studies in this branch of biology examine such phenomena as Adaptation (biology), adaptation, s ...

study of representative freshwater and migratory individuals has probed deeper into the molecular mechanisms of migratory adaptation.

References

nasus Fish of the Pacific Ocean Fish of Korea Oily fish Taxa named by Coenraad Jacob Temminck Taxa named by Hermann Schlegel Fish described in 1846 {{Clupeiformes-stub