The Bathydraconidae, or the Antarctic dragonfishes, are a
family
Family (from la, familia) is a group of people related either by consanguinity (by recognized birth) or affinity (by marriage or other relationship). The purpose of the family is to maintain the well-being of its members and of society. Idea ...
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 h ...
es, notothenioids belonging to the
Perciform
Perciformes (), also called the Percomorpha or Acanthopteri, is an order or superorder of ray-finned fish. If considered a single order, they are the most numerous order of vertebrates, containing about 41% of all bony fish. Perciformes means " ...
suborder Notothenioidei
Notothenioidei is one of 19 suborders of the order Perciformes. The group is found mainly in Antarctic and Subantarctic waters, with some species ranging north to southern Australia and southern South America. Notothenioids constitute approx ...
. The family comprises four genera. These fishes are endemic to deep waters off
Antarctica
Antarctica () is Earth's southernmost and least-populated continent. Situated almost entirely south of the Antarctic Circle and surrounded by the Southern Ocean, it contains the geographic South Pole. Antarctica is the fifth-largest cont ...
.
[
]
Taxonomy
Bathydraconidae was first formally described as a family in 1913 by the English
English usually refers to:
* English language
* English people
English may also refer to:
Peoples, culture, and language
* ''English'', an adjective for something of, from, or related to England
** English national ide ...
ichthyologist Charles Tate Regan
Charles Tate Regan FRS (1 February 1878 – 12 January 1943) was a British ichthyologist, working mainly around the beginning of the 20th century. He did extensive work on fish classification schemes.
Born in Sherborne, Dorset, he was educat ...
in his report on the fishes collected on the Scottish National Antarctic Expedition
The Scottish National Antarctic Expedition (SNAE), 1902–1904, was organised and led by William Speirs Bruce, a natural scientist and former medical student from the University of Edinburgh. Although overshadowed in terms of prestige by Rob ...
to the Royal Society of Edinburgh.[ He used the genus '' Bathydraco'', which had been described by ]Albert Gunther
Albert may refer to:
Companies
* Albert (supermarket), a supermarket chain in the Czech Republic
* Albert Heijn, a supermarket chain in the Netherlands
* Albert Market, a street market in The Gambia
* Albert Productions, a record label
* Alber ...
in 1878 as a 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 "unispe ...
genus
Genus ( plural genera ) is a taxonomic rank used in the biological classification of living and fossil organisms as well as viruses. In the hierarchy of biological classification, genus comes above species and below family. In binomial nom ...
with '' B. antarctica'' as its type species
In zoological nomenclature, a type species (''species typica'') is the species name with which the name of a genus or subgenus is considered to be permanently taxonomically associated, i.e., the species that contains the biological type specime ...
, as the type genus
In biological taxonomy, the type genus is the genus which defines a biological family and the root of the family name.
Zoological nomenclature
According to the International Code of Zoological Nomenclature, "The name-bearing type of a nominal ...
. Molecular analyses have supported the split of bathydraconids into three clades
A clade (), also known as a monophyletic group or natural group, is a group of organisms that are monophyletic – that is, composed of a common ancestor and all its lineal descendants – on a phylogenetic tree. Rather than the English term, ...
; Bathydraconinae which includes ''Bathydraco'', '' Prionodraco'' and '' Racovitzia''; Gymnodraconinae which includes '' Gymnodraco'', '' Psilodraco'' and '' Acanthodraco''); and Cygnodraconinae including '' Cygnodraco'', '' Gerlachea'' and '' Parachaenichthys''. However, this subdivision is not recognised in the 5th edition of '' Fishes of the World''. The name of the family is derived from the generic name ''Bathydraco'' which is a combination of ''bathy'' meaning "deep" and ''draco'' meaning dragon, the type of ''B. antarctica'' was collected at and ''draco'' is a commonly used suffix for Notothenioids.
Genera
The following genera are classified within the family Bathydraconidae:
* '' Acanthodraco'' Skóra, 1995
* '' Akarotaxis'' DeWitt & Hureau, 1980
* '' Bathydraco'' Günther, 1878
* '' Cygnodraco'' Waite, 1916
* '' Gerlachea'' Dollo, 1900
* '' Gymnodraco'' Boulenger, 1902
* '' Parachaenichthys'' Boulenger, 1902
* '' Prionodraco'' Regan, 1914
* '' Psilodraco'' Norman
Norman or Normans may refer to:
Ethnic and cultural identity
* The Normans, a people partly descended from Norse Vikings who settled in the territory of Normandy in France in the 10th and 11th centuries
** People or things connected with the Norm ...
. 1937
* '' Racovitzia'' Dollo, 1900
* '' Vomeridens'' DeWitt & Hureau, 1980
Characteristics
Bathydraconidae species have elongate, slender bodies and may be separated from the other notothenioid families by the lack of a spiny first dorsal fin. Their bodies may be stocky, nearly cylindrical or rather depressed at the front and compressed at the rear. There is a single dorsal fin
A dorsal fin is a fin located on the back of most marine and freshwater vertebrates within various taxa of the animal kingdom. Many species of animals possessing dorsal fins are not particularly closely related to each other, though through c ...
which has a long base and lacks any spines. The anal fin is typically shorter based than the dorsal fin, again having no spines. 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 are well developed while the pelvic fins contain 1 spine and 5 branched fin rays, beginning to the front of the pectoral fins. The head is moderate to large in size, being depressed in some species. They have a long snout which is flattened or even slightly depressed and is typically short and pointed. They have large mouths which can extend as far as the level of the middle of the eye. The jaws normally have small, conical teeth and occasionally canines, there are usually no teeth elsewhere in the mouth. They have a single external nostril. The operculum may have a rearwards directed hooked or spine, it may be unarmed. The bodies may have scales, typically ctenoid
A fish scale is a small rigid plate that grows out of the skin of a fish. The skin of most jawed fishes is covered with these protective scales, which can also provide effective camouflage through the use of reflection and colouration, as ...
, bony plates or be naked. They can have 1, 2, 3 or 5 lateral lines made up of tubular, pored or pitted scales, and these are occasionally interlinked.
Distribution, habitat and biology
Bathydraconidae species are 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 ...
fishes found in Antarctic waters. They are not fished commercially and little is known about them. The majority of species in this group occur over the continental shelf and slope of Antarctica, but some have been reported from the Antarctic and sub-Antarctic Islands. They inhabit from shallow, inshore waters, although some have been found as deep as . One species, '' Gymnodraco acuticeps'', has been found in McMurdo Sound
McMurdo Sound is a sound in Antarctica. It is the southernmost navigable body of water in the world, and is about from the South Pole.
Captain James Clark Ross discovered the sound in February 1841, and named it after Lt. Archibald McMurdo ...
living at shallow depths under sea ice, this species may even live under the Ross Ice Shelf.[
]
References
{{Taxonbar, from=Q571470
Notothenioidei