''Sebastes inermis'', the Japanese red seaperch or dark-banded rockfish, is a

species In biology, a species is the basic unit of classification and a taxonomic rank of an organism, as well as a unit of biodiversity. A species is often defined as the largest group of organisms in which any two individuals of the appropriate s ...

of marine

ray-finned fish Actinopterygii (; ), members of which are known as ray-finned fishes, is a class of bony fish. They comprise over 50% of living vertebrate species. The ray-finned fishes are so called because their fins are webs of skin supported by bony or hor ...

belonging to the subfamily Sebastinae, the rockfishes, part of the

family Family (from la, familia) is a Social group, group of people related either by consanguinity (by recognized birth) or Affinity (law), affinity (by marriage or other relationship). The purpose of the family is to maintain the well-being of its ...

Scorpaenidae The Scorpaenidae (also known as scorpionfish) are a family of mostly marine fish that includes many of the world's most venomous species. As their name suggests, scorpionfish have a type of "sting" in the form of sharp spines coated with venom ...

. It is found in the northwestern

Pacific Ocean The Pacific Ocean is the largest and deepest of Earth's five oceanic divisions. It extends from the Arctic Ocean in the north to the Southern Ocean (or, depending on definition, to Antarctica) in the south, and is bounded by the continen ...

. This species is known as ''mebaru'' ( メバル/鮴) in Japan and as ''bollak'' (볼락) in Korea.

Taxonomy

''Sebastes inermis'' was first formally described in 1829 by the French

zoologist Zoology ()The pronunciation of zoology as is usually regarded as nonstandard, though it is not uncommon. is the branch of biology that studies the Animal, animal kingdom, including the anatomy, structure, embryology, evolution, Biological clas ...

Georges Cuvier Jean Léopold Nicolas Frédéric, Baron Cuvier (; 23 August 1769 – 13 May 1832), known as Georges Cuvier, was a French natural history, naturalist and zoology, zoologist, sometimes referred to as the "founding father of paleontology". Cuvier ...

with the type locality given as Japan. Together with '' S. ventricosus'' and '' S. cheni'' these three taxa form a species complex and have been treated as a single species in the past. Some authorities place this species complex in the

subgenus In biology, a subgenus (plural: subgenera) is a taxonomic rank directly below genus. In the International Code of Zoological Nomenclature, a subgeneric name can be used independently or included in a species name, in parentheses, placed between t ...

''Mebarus''. The

specific name Specific name may refer to: * in Database management systems, a system-assigned name that is unique within a particular database In taxonomy, either of these two meanings, each with its own set of rules: * Specific name (botany), the two-part (bino ...

''inermis'' means “unarmed”, a reference to the relatively small spines on the head.

Description

''Sebastes inermis'' has sharp lachrymal spines with the rest of the spines on the head are rather weak. The caudal fin is not strongly emarginate. It has a dark red or pale brown body on the back and flanks. The

pectoral fin Fins are distinctive anatomical features composed of bony spines or rays protruding from the body of a fish. They are covered with skin and joined together either in a webbed fashion, as seen in most bony fish, or similar to a flipper, as ...

s reach beyond the level of the anus when held down., The pectoral fins have 15 rays while the

anal fin Fins are distinctive anatomical features composed of bony spines or rays protruding from the body of a fish. They are covered with skin and joined together either in a webbed fashion, as seen in most bony fish, or similar to a flipper, as se ...

has 7 rays. This species grows to a total length of , and the heaviest recorded specimen weighed .

Distribution and habitat

''Sebastes inermis'' it occurs from southern

Hokkaido is Japan's second largest island and comprises the largest and northernmost prefecture, making up its own region. The Tsugaru Strait separates Hokkaidō from Honshu; the two islands are connected by the undersea railway Seikan Tunnel. The la ...

southward to

Kyushu is the third-largest island of Japan's five main islands and the most southerly of the four largest islands ( i.e. excluding Okinawa). In the past, it has been known as , and . The historical regional name referred to Kyushu and its surroun ...

, Japan, and the southern part of the Korean Peninsula. It is a

demersal fish Demersal fish, also known as groundfish, live and feed on or near the bottom of seas or lakes (the demersal zone).Walrond Carl . "Coastal fish - Fish of the open sea floor"Te Ara - the Encyclopedia of New Zealand. Updated 2 March 2009 They occ ...

with pelagic juveniles which live among floating mats of seaweeds.

Biology

''Sebastes inermis'' feeds on zooplankton. Males are territorial, establishing territories which range in area from . The male initiates courtship when a female approaches their territory and perform a lateral display with rushing and turning movements being recorded frequently as part of the courtship. The courtship behaviour lasts for around 30 minutes before copulation. It climaxes with the pair ascending into the water column, above the seabed, the male suddenly coils around the body of the female to copulate.

Human usage

''Sebastes inermis'' is one of the most important target species for fisheries in Japan and is also grown in aquaculture to supply market demand.

Sea perch fishing

Sea perch are very popular seawater game fish highly prized especially by fishermen, because they generally put up a good fight when caught with a hook and line. As sea perch are predatory fish, lure fishing (which use replica baits called lures to imitate live prey) is the predominant form of sport fishing involving sea perch, although traditional bait fishing techniques using floats and/or sinkers (particularly with moving live baits such as baitfish, krill or shrimp) are also successful. It is recommended that when fishing for sea perch, that the fisher(s) should use line in the 1–5 lb test for sea perch. It is also recommended to use a hook size 8-5 for sea perch of all kind. Sea perch, tend to like ragworms, minnows, or cut bait.

References

{{Authority control inermis Game fish Fish of Korea Taxa named by Georges Cuvier Fish described in 1829