Mawson's dragonfish (''Cygnodraco mawsoni'') 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 Antarctic dragonfish native to the

Southern Ocean The Southern Ocean, also known as the Antarctic Ocean, comprises the southernmost waters of the World Ocean, generally taken to be south of 60° S latitude and encircling Antarctica. With a size of , it is regarded as the second-small ...

around

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 ...

. It is found at depths of from over the continental shelf. This species is the only known member of its

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 ...

Taxonomy

Mawson’s dragonfish was first formally described in 1916 by the British-born Australian ichthyologist Edgar Ravenswood Waite with the type locality given as Queen Mary Land off

Drygalski Island Drygalski Island is an ice-capped island that is long and rises to in the Davis Sea of the Southern Ocean, about north of the coast of Queen Mary Land and north-northeast of Cape Filchner. The island has an area of . Drygalski Island was f ...

where it was collected by the

Australian Antarctic Expedition The Australasian Antarctic Expedition was a 1911–1914 expedition headed by Douglas Mawson that explored the largely uncharted Antarctic coast due south of Australia. Mawson had been inspired to lead his own venture by his experiences on Erne ...

. Waite described it as the only species in 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. The genus name is a combination of ''cygnus'' meaning “swan”, an allusion Waite did not explain but may be a reference to the somewhat duck-bill shaped snout, and ''draco'' which means “dragon”, a common suffix used In Notothenioid fishes. The specific name honours the Australian

geologist A geologist is a scientist who studies the solid, liquid, and gaseous matter that constitutes Earth and other terrestrial planets, as well as the processes that shape them. Geologists usually study geology, earth science, or geophysics, althoug ...

Douglas Mawson Sir Douglas Mawson OBE FRS FAA (5 May 1882 – 14 October 1958) was an Australian geologist, Antarctic explorer, and academic. Along with Roald Amundsen, Robert Falcon Scott, and Sir Ernest Shackleton, he was a key expedition leader duri ...

who led the Australasian Antarctic Expedition.

Description

Mawson’s dragonfish has a slender, naked body with the only scales being in the two lateral lines,the upper lateral line is wholly made up of perforated scales. There is a flattened ridge on the operculum which divides towards the margin. They have a thin band of conical teeth in the jaws. The

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 ...

has 61-66 soft rays while the anal fin has 36-38. In alcohol the overall colour is brown with darker saddles and bars, the median fins are darker than the

pectoral Pectoral may refer to: * The chest region and anything relating to it. * Pectoral cross, a cross worn on the chest * a decorative, usually jeweled version of a gorget * Pectoral (Ancient Egypt), a type of jewelry worn in ancient Egypt * Pectorali ...

and pelvic fins. This species grows to a length of standard length.

Distribution and habitat

Mawson’s dragonfish is found in the Southern Ocean over the Antarctic continental shelf. It is a demersal species found at depths of .

Biology

Mawson’s dragonfish in the

Weddell Sea The Weddell Sea is part of the Southern Ocean and contains the Weddell Gyre. Its land boundaries are defined by the bay formed from the coasts of Coats Land and the Antarctic Peninsula. The easternmost point is Cape Norvegia at Princess Martha ...

are adult at and start breeding at . Spawning takes place during the autumn and early winter. They feed largely on benthic and

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 ...

organisms such as fishes, especially rockcods in the genus ''

Trematomus ''Trematomus'' is a genus of marine ray-finned fishes, belonging to the Family (biology), family Nototheniidae, the notothens or cod icefishes. These fishes occur in the Southern Ocean. Taxonomy ''Trematomus'' was first described as a genus in 1 ...

'' and the decapod '' Crangon antarcticus'' as well as ''mysids'', gammarids and

polychaetes Polychaeta () is a paraphyletic class of generally marine annelid worms, commonly called bristle worms or polychaetes (). Each body segment has a pair of fleshy protrusions called parapodia that bear many bristles, called chaetae, which are made ...

References

{{Taxonbar, from=Q2037719 Bathydraconidae Monotypic fish genera Fish of Antarctica Fish described in 1916 Taxa named by Edgar Ravenswood Waite