The Korean sandlance (''Hypoptychus dybowskii'') is a
species
A species () is often defined as the largest group of organisms in which any two individuals of the appropriate sexes or mating types can produce fertile offspring, typically by sexual reproduction. It is the basic unit of Taxonomy (biology), ...
of marine
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 ...
belonging to the
family
Family (from ) is a Social group, group of people related either by consanguinity (by recognized birth) or Affinity (law), affinity (by marriage or other relationship). It forms the basis for social order. Ideally, families offer predictabili ...
Hypoptychidae
The Korean sandlance (''Hypoptychus dybowskii'') is a species of marine ray-finned fish belonging to the family Hypoptychidae. The Korean sandlance is the only species in this monotypic family and genus and is found in the northwestern Pacific O ...
. The Korean sandlance is the only species in this
monotypic
In biology, a monotypic taxon is a taxonomic group (taxon) that contains only one immediately subordinate taxon. A monotypic species is one that does not include subspecies or smaller, infraspecific taxa. In the case of genera, the term "unisp ...
family and
genus
Genus (; : genera ) is a taxonomic rank above species and below family (taxonomy), family as used in the biological classification of extant taxon, living and fossil organisms as well as Virus classification#ICTV classification, viruses. In bino ...
and is found in the northwestern Pacific Ocean.
Taxonomy
The Korean sandlance was first formally
described in 1880 by the Austrian
ichthyologist
Ichthyology is the branch of zoology devoted to the study of fish, including bony fish (Osteichthyes), cartilaginous fish (Chondrichthyes), and jawless fish (Agnatha). According to FishBase, 35,800 species of fish had been described as of March 2 ...
Franz Steindachner
Franz Steindachner (11 November 1834 in Vienna – 10 December 1919 in Vienna) was an Austrian zoologist, ichthyologist, and herpetologist. He published over 200 papers on fishes and over 50 papers on reptiles and amphibians. Steindachner des ...
with its
type locality given as
Peter the Great Bay
The Peter the Great Gulf (Russian: Залив Петра Великого) is a gulf on the southern coast of Primorsky Krai, Russia, and the largest gulf of the Sea of Japan. The gulf extends for from the Russian–North Korean border, at the ...
.
Steindachner also classified in the
monospecific
In biology, a monotypic taxon is a taxonomic group (taxon) that contains only one immediately subordinate taxon. A monotypic species is one that does not include subspecies or smaller, infraspecific taxa. In the case of genera, the term "unispe ...
genus ''Hypoptychus'' and in the
monogeneric
In biology, a monotypic taxon is a taxonomic group (taxon) that contains only one immediately subordinate taxon. A monotypic species is one that does not include subspecies or smaller, infraspecific taxa. In the case of genera, the term "unispe ...
family Hypoptychidae.
This family described a monotypic and is included in the suborder
Gasterosteoidei
Gasterosteoidei is a suborder of ray-finned fishes that includes the sticklebacks and relatives, the 5th edition of ''Fishes of the World'' classifies this suborder within the order Scorpaeniformes.
Systematics
Gasterosteoidei is treated as ...
of the
order
Order, ORDER or Orders may refer to:
* A socio-political or established or existing order, e.g. World order, Ancien Regime, Pax Britannica
* Categorization, the process in which ideas and objects are recognized, differentiated, and understood
...
Scorpaeniformes
The Scorpaeniformes are a diverse Order (biology), order of Actinopterygii, ray-finned fish, including the lionfishes and sculpins, but have also been called the Scleroparei. It is one of the five largest orders of bony fishes by number of spec ...
in the 5th edition of ''
Fishes of the World
''Fishes of the World'' is a standard reference for the systematics of fishes. It was first written in 1976 by the American ichthyologist Joseph S. Nelson (1937–2011). Now in its fifth edition (2016), the work is a comprehensive overview of t ...
''.
Other authorities treat the Gasterosteoidei as the
infraorder
Order () is one of the eight major hierarchical taxonomic ranks in Linnaean taxonomy. It is classified between Family_(biology), family and Class_(biology), class. In biological classification, the order is a taxonomic rank used in the classific ...
Gasterosteales within the suborder
Cottoidei
Cottoidei is a suborder of ray-finned fishes which, according to the 5th edition of ''Fishes of the World'', is placed within the order Scorpaeniformes, alongside the scorpionfishes, flatheads, eelpouts, sticklebacks and related fishes.
Taxon ...
or as a sister clade to the
Zoarcales in the order Zoarciformes.
Some authorities include the tubenose (''
Aulichthys japonicus
''Aulichthys'' is a monospecific genus of marine ray-finned fish belonging to the family Aulorhynchidae. Its only species is ''Aulichthys japonicus'', the tubenose, which is found in the shallow waters on the coasts of Japan, China and the Korea ...
'') in the Hypoptychidae,
but the 5th edition of ''Fishes of the World'' puts this taxon in the family Aulorhynchidae
Aulorhynchidae, the tube-snouts, is a small Family (biology), family of marine ray-finned fishes belonging to the suborder Gasterosteoidei in the Order (biology), order Perciformes. These fishes are found in the northern Pacific Ocean.
Taxonomy
...
.[
]
Etymology
The Korean sandlance's genus name, ''Hypoptychus'', is a combination of ''hypo'', which means "under", and ''ptychos'', meaning "fold", an allusion to the long skin fin fold on the lower surface of the body in that taxon. 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 ...
likely honours the Polish biologist Benedykt Dybowski
Benedykt Tadeusz Dybowski (12 May 183331 January 1930) was a Polish naturalist and physician.
Life
Benedykt Dybowski was born in Adamaryni, within the Minsk Governorate of the Russian Empire to Polish nobility. He was the brother of naturalis ...
, who was a worker on the fauna of the Russian Far East
The Russian Far East ( rus, Дальний Восток России, p=ˈdalʲnʲɪj vɐˈstok rɐˈsʲiɪ) is a region in North Asia. It is the easternmost part of Russia and the Asia, Asian continent, and is coextensive with the Far Easte ...
.
Description
The Korean sandlance has an elongate body which has no scales, scutes or spines. Its dorsal
Dorsal (from Latin ''dorsum'' ‘back’) may refer to:
* Dorsal (anatomy), an anatomical term of location referring to the back or upper side of an organism or parts of an organism
* Dorsal, positioned on top of an aircraft's fuselage
The fus ...
and anal fin
Fins are moving appendages protruding from the body of fish that interact with water to generate thrust and help the fish swim. Apart from the tail or caudal fin, fish fins have no direct connection with the back bone and are supported o ...
s are placed well back on the body towards the caudal fin
Fins are moving appendages protruding from the body of fish that interact with water to generate thrust and help the fish swim. Apart from the tail or caudal fin, fish fins have no direct connection with the back bone and are supported only ...
, and they both have around 20 fin rays. There is no pelvic girdle or pelvic fins. The pectoral fin
Fins are moving appendages protruding from the body of fish that interact with water to generate thrust and help the fish aquatic locomotion, swim. Apart from the tail or caudal fin, fish fins have no direct connection with the vertebral column ...
has 9 rays and the caudal fin has 13 main rays, 11 of which are branched. There is a broken ring around the eye. In males the premaxilla has teeth but not in females. There are around 29 pairs of pleural rib
The pleural cavity, or pleural space (or sometimes intrapleural space), is the potential space between the pleurae of the pleural sac that surrounds each lung. A small amount of serous pleural fluid is maintained in the pleural cavity to enable ...
s, but there are no epipleurals, the vertebrae
Each vertebra (: vertebrae) is an irregular bone with a complex structure composed of bone and some hyaline cartilage, that make up the vertebral column or spine, of vertebrates. The proportions of the vertebrae differ according to their spinal ...
number roughly 55 to 57. The hypural plate is split into upper and lower halves, on most other members of the suborder, the other exception being the sticklebacks in the genus ''Gasterosteus
''Gasterosteus'' is a genus of ray-finned fishes belonging to the Family (biology), family Gasterosteidae, the sticklebacks. These fishes are found in freshwater, brackish water and marine habitats in the Holarctic realm, Holarctic region.
Speci ...
'' the hypural plate is fused.[ This species has a maximum published ]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 ...
of . The smeitransparent head and body are reddish-yellow in colour marked with small black spot, these are larger around the front of the lower jaw and on the lower gill membrane. The fins are all semi-transparent and the membranes of dorsal and anal fins have small black melanophore
Chromatophores are cells that produce color, of which many types are pigment-containing cells, or groups of cells, found in a wide range of animals including amphibians, fish, reptiles, crustaceans and cephalopods. Mammals and birds, in contrast ...
s.[
]
Distribution and habitat
The Korean sandlance is found in the northwestern Pacific Ocean where it occurs in the coastal waters off of northern Honshu
, historically known as , is the largest of the four main islands of Japan. It lies between the Pacific Ocean (east) and the Sea of Japan (west). It is the list of islands by area, seventh-largest island in the world, and the list of islands by ...
and Hokkaido
is the list of islands of Japan by area, second-largest island of Japan and comprises the largest and northernmost prefectures of Japan, prefecture, making up its own list of regions of Japan, region. The Tsugaru Strait separates Hokkaidō fr ...
in Japan, Sakhalin
Sakhalin ( rus, Сахали́н, p=səxɐˈlʲin) is an island in Northeast Asia. Its north coast lies off the southeastern coast of Khabarovsk Krai in Russia, while its southern tip lies north of the Japanese island of Hokkaido. An islan ...
, and the Kuril Islands
The Kuril Islands or Kurile Islands are a volcanic archipelago administered as part of Sakhalin Oblast in the Russian Far East. The islands stretch approximately northeast from Hokkaido in Japan to Kamchatka Peninsula in Russia, separating the ...
.[ Its presence off the Korean coast has been confirmed.] It is a benthopelagic
The demersal zone is the part of the sea or ocean (or deep lake) consisting of the part of the water column near to (and significantly affected by) the seabed and the benthos. The demersal zone is just above the benthic zone and forms a layer of ...
species.[
]
Biology
The Korean sandlance forms school
A school is the educational institution (and, in the case of in-person learning, the Educational architecture, building) designed to provide learning environments for the teaching of students, usually under the direction of teachers. Most co ...
s of between 100 and 500 individuals. It is a major prey species for rockfishes and greenlings. Spawning
Spawn is the Egg cell, eggs and Spermatozoa, sperm released or deposited into water by aquatic animals. As a verb, ''to spawn'' refers to the process of freely releasing eggs and sperm into a body of water (fresh or marine); the physical act is ...
takes place from mid-April to late June, and the healthy males are territorial
A territory is an area of land, sea, or space, belonging or connected to a particular country, person, or animal.
In international politics, a territory is usually a geographic area which has not been granted the powers of self-government, ...
but males which are less fit become "sneaker males wiktionary:sneaker male, i.e. pretending to be female to gain access to the females without defending a territory. The territorial males display to attract females, the female approaches the male's territory and lays eggs on the branching points of Sargassaceae
Sargassaceae is a family of brown algae in the order Fucales
The Fucales (fucoids) are an order in the brown algae (class Phaeophyceae). The list of families in the Fucales, as well as additional taxonomic information on algae, is publicly a ...
seaweed
Seaweed, or macroalgae, refers to thousands of species of macroscopic, multicellular, marine algae. The term includes some types of ''Rhodophyta'' (red), '' Phaeophyta'' (brown) and ''Chlorophyta'' (green) macroalgae. Seaweed species such as ...
, e.g. ''Sargassum horneri
''Sargassum horneri'' is a species of brown macroalgae that is common along the coast of Japan and Korea. It is an annual algae which has a varying fertile season along the coast. In Wakasa Bay, Japan it begins to grow in early autumn through wi ...
'' or ''Cystoseira hakodatensis
''Cystoseira'' is a genus of brown algae in the order Fucales.
Description
As presently defined, ''Cystoseira'' comprises fucoids characterised by antherozoids without stigmata, few antheridial branches, trichothallic hairs in conceptacles, la ...
''. Study of the otolith
An otolith (, ' ear + , ', a stone), also called otoconium, statolith, or statoconium, is a calcium carbonate structure in the saccule or utricle (ear), utricle of the inner ear, specifically in the vestibular system of vertebrates. The saccule ...
s has shown that this species lives up to a year old,[ Like sticklebacks, it feeds on small invertebrates and fish larvae. Also like sticklebacks, it produces a sticky secretion from its ]kidney
In humans, the kidneys are two reddish-brown bean-shaped blood-filtering organ (anatomy), organs that are a multilobar, multipapillary form of mammalian kidneys, usually without signs of external lobulation. They are located on the left and rig ...
s when breeding. The parent uses the secretion to attach the eggs
An egg is an organic vessel in which an embryo begins to develop.
Egg, EGG or eggs may also refer to:
Biology
* Egg cell, the female reproductive cell (gamete) in oogamous organisms
Food
* Eggs as food
Places
* Egg, Austria
* Egg, Switzerland ...
to sargassum
''Sargassum'' is a genus of brown macroalgae ( seaweed) in the order Fucales of the Phaeophyceae class. Numerous species are distributed throughout the temperate and tropical oceans of the world, where they generally inhabit shallow water and ...
.
Utilisation
The Korean sandlance is fished for by commercial fisheries, however there is little information on the extent of this, or even on whether this still occurs.[
]
References
{{Taxonbar, from1=Q680198, from2=Q19827844, from3=Q2683197
Gasterosteoidei
Fish described in 1880
Taxa named by Franz Steindachner