''Dolloidraco'' is 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 "unisp ...

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 ...

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 ...

, its only known species being ''Dolloidraco longedorsalis'', 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 ...

Artedidraconidae, the barbeled plunderfishes. It is 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 60th parallel south, 60° S latitude and encircling Antarctica. With a size of , it is the seco ...

in the waters 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 (also known as the Antarctic Ocean), it contains the geographic South Pole. ...

Taxonomy

''Dolloidraco'' was first formally described as a genus in 1913 by the French

zoologist Zoology ( , ) is the scientific study of animals. Its studies include the structure, embryology, classification, habits, and distribution of all animals, both living and extinct, and how they interact with their ecosystems. Zoology is one ...

Louis Roule in his

description Description is any type of communication that aims to make vivid a place, object, person, group, or other physical entity. It is one of four rhetorical modes (also known as ''modes of discourse''), along with exposition, argumentation, and narr ...

of ''D. longedorsalis'' which had been collected on the

French Antarctic Expedition The French Antarctic Expedition is any of several French expeditions in Antarctica. 1837–1840 In 1837, during an 1837–1840 expedition across the deep southern hemisphere, Captain Jules Dumont d'Urville sailed his ship ''Astrolabe'' alo ...

led by

Jean-Baptiste Charcot Jean-Baptiste Étienne Auguste Charcot, better known in France as Commandant Charcot, (15 July 1867 in Neuilly-sur-Seine near Paris – 16 September 1936 at sea (30 miles north-west of Reykjavik, Iceland), was a French scientist, medical doctor ...

from 1904-1907. The type locality was given as

Marguerite Bay Marguerite Bay or Margaret Bay is an extensive bay on the west side of the Antarctic Peninsula, which is bounded on the north by Adelaide Island and on the south by Wordie Ice Shelf, George VI Sound and Alexander Island. The mainland coast on th ...

and Jenny Island on the

Antarctic Peninsula The Antarctic Peninsula, known as O'Higgins Land in Chile and Tierra de San Martin in Argentina, and originally as Graham Land in the United Kingdom and the Palmer Peninsula in the United States, is the northernmost part of mainland Antarctica. ...

. The generic name compounds Dollo, honouring the Belgian

paleontologist Paleontology, also spelled as palaeontology or palæontology, is the scientific study of the life of the past, mainly but not exclusively through the study of fossils. Paleontologists use fossils as a means to classify organisms, measure geolo ...

Louis Dollo who published on Antarctic fishes, with ''draco'', a reference to the related genus '' Artedidraco''. The specific name is a compound of ''longi'' which means "long" and ''dorsalis'' meaning "dorsal". Roule did not explain this but it may be a reference to this taxon's taller, but not longer,

dorsal fin A dorsal fin is a fin on the back of most marine and freshwater vertebrates. Dorsal fins have evolved independently several times through convergent evolution adapting to marine environments, so the fins are not all homologous. They are found ...

in comparison with ''Artedidraco''.

Description

''Dolloidraco'' has a first dorsal fin which contains 3-4 spines and is located over the operculum, the second dorsal fin contains 22-25 soft rays while the

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 ...

has 14-16 soft rays. 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 ...

has 8-10 branched rays and 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 ...

contains 16-18 fin rays. The head has a width which is roughly the same as their depth and the post temporal ridges are weakly developed. The snout is shorter than the diameter of the eye and the space between the eyes is narrow. The mental

barbel Barbel may refer to: *Barbel (anatomy), a whisker-like organ near the mouth found in some fish (notably catfish, loaches and cyprinids) and turtles *Barbel (fish), a common name for certain species of fish **''Barbus barbus'', a species of cyprini ...

, the barbel on the chin which characterises the barbeled plunderfishes, is tapered or expanded towards its tip. The upper

lateral line The lateral line, also called the lateral line organ (LLO), is a system of sensory organs found in fish, used to detect movement, vibration, and pressure gradients in the surrounding water. The sensory ability is achieved via modified epithelia ...

has tubed scales at the head end and towards the caudal fin it normally has disc shaped scales, the middle lateral line consist of disc-shaped scales. This species attains a maximum

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 .

Distribution, habitat and biology

''Dolloidraco'' is found in the Southern Ocean where it has been recorded from 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 C ...

Graham Land Graham Land is the portion of the Antarctic Peninsula that lies north of a line joining Cape Jeremy and Cape Agassiz. This description of Graham Land is consistent with the 1964 agreement between the British Antarctic Place-names Committee ...

Queen Mary Land Queen Mary Land or the Queen Mary Coast () is the portion of the coast of Antarctica lying between Cape Filchner, in 91° 54' E, and Cape Hordern, at 100° 30' E. It is claimed by Australia as part of the Australian Antarctic Territory. It ...

and south

Victoria Land Victoria Land is a region in eastern Antarctica which fronts the western side of the Ross Sea and the Ross Ice Shelf, extending southward from about 70°30'S to 78th parallel south, 78°00'S, and westward from the Ross Sea to the edge of the Ant ...

. It is a

bathydemersal Demersal fish, also known as groundfish, live and feed on or near the bottom of ocean, 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 T ...

species which is found at depths of in the

sublittoral The littoral zone, also called litoral or nearshore, is the part of a sea, lake, or river that is close to the shore. In coastal ecology, the littoral zone includes the intertidal zone extending from the high water mark (which is rarely in ...

and

continental shelf A continental shelf is a portion of a continent that is submerged under an area of relatively shallow water, known as a shelf sea. Much of these shelves were exposed by drops in sea level during glacial periods. The shelf surrounding an islan ...

. Their diet is dominated by errant

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 m ...

with gammaridean amphipods,

isopods Isopoda is an Order (biology), order of crustaceans. Members of this group are called isopods and include both Aquatic animal, aquatic species and Terrestrial animal, terrestrial species such as woodlice. All have rigid, segmented exoskeletons ...

, sedentary polychaetes, and unidentified polychaetes eaten as secondary items. Calanoid copepods, unidentified crustaceans,

cumacea Cumacea is an order (biology), order of small marine crustaceans of the superorder Peracarida, occasionally called hooded shrimp or comma shrimp. Their unique appearance and uniform body plan makes them easy to distinguish from other crustaceans. ...

ns, hydroids, and mysids are consumed but are not important parts of the diet.

References

{{Taxonbar, from=Q2301500 Artedidraconidae Taxa named by Louis Roule Fish described in 1913 Monotypic fish genera