''Channichthys richardsoni'', the robust icefish, is a

demersal 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 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

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 ...

Channichthyidae, the

crocodile icefish The crocodile icefish or white-blooded fish comprise a family (Channichthyidae) of notothenioid fish found in the Southern Ocean around Antarctica. They are the only known vertebrates to lack hemoglobin in their blood as adults. Icefish populatio ...

es. It is

endemic Endemism is the state of a species being found in a single defined geographic location, such as an island, state, nation, country or other defined zone; organisms that are indigenous to a place are not endemic to it if they are also found elsew ...

to the

shelf Shelf ( : shelves) may refer to: * Shelf (storage), a flat horizontal surface used for display and storage Geology * Continental shelf, the extended perimeter of a continent, usually covered by shallow seas * Ice shelf, a thick platform of ice f ...

waters of the

Kerguelen Islands The Kerguelen Islands ( or ; in French commonly ' but officially ', ), also known as the Desolation Islands (' in French), are a group of islands in the sub-Antarctic constituting one of the two exposed parts of the Kerguelen Plateau, a large ...

in 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 ...

. It lives at depths of .

Taxonomy

The species name is given in honour of the Scottish naturalist John Richardson, who described the first species of icefish ''

Channichthys rhinoceratus ''Channichthys rhinoceratus,'' the unicorn icefish, is a species of marine ray-finned fish belonging to the Family (biology), family Channichthyidae, the crocodile icefishes. It is Endemism, endemic to the Kerguelen Plateau, Kerguelen-Heard Plat ...

,'' and established the genus ''Channichthys''.

Fishbase FishBase is a global species database of fish species (specifically finfish). It is the largest and most extensively accessed online database on adult finfish on the web.

treats it as a valid species but '' Catalog of Fishes'' treats it as a

junior synonym The Botanical and Zoological Codes of nomenclature treat the concept of synonymy differently. * In botanical nomenclature, a synonym is a scientific name that applies to a taxon that (now) goes by a different scientific name. For example, Linna ...

of '' C. rhinoceratus''.

Description

This heavy-bodied species is dark grey to brown in coloration and has 3-4 dark cross bars on its body. There are up to 6 narrow dark stripes on the

caudal fins Fins are distinctive anatomical features composed of bony spine (zoology), spines or Ray (fish fin anatomy), 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 bon ...

and

pelvic fins Pelvic fins or ventral fins are paired fins located on the ventral surface of fish. The paired pelvic fins are homologous to the hindlimbs of tetrapods. Structure and function Structure In actinopterygians, the pelvic fin consists of two en ...

. Dark spots and blotches are present on the ventral part of body and head. The lower jaw extends to about one-third to half of the eye diameter below the eye. It is distinguished from other ''

Channichthys ''Channichthys'' is a genus of marine ray-finned fish belonging to the family Channichthyidae, the crocodile icefishes. They are native to the Southern Ocean. Taxonomy ''Channichthys'' was first formally described as a genus in 1844 by the Scot ...

'' species (to whom it is very similar with) by the moderate size of its eyes, number of gill rakers on the lower arch (6-15), longer snout (approximately equal to half the length of the head) and other characteristics, such as the relatively robust body compared to other ''Channichthys'' species (which gave this species its common name) and relatively small eye (in some specimens just reaching 33% of snout length). The maximum size recorded for this species was a post-spawning female of size . It is a

piscivorous A piscivore () is a carnivorous animal that eats primarily fish. The name ''piscivore'' is derived . Piscivore is equivalent to the Greek-derived word ichthyophage, both of which mean "fish eater". Fish were the diet of early tetrapod evoluti ...

(fish-eating) species. Maturity is reached at in females. Spawning occurs from autumn to early winter. This species is of no interest to commercial fisheries.

References

richardsoni Fauna of the Kerguelen Islands Fish of the Southern Ocean Fish described in 2011 {{Channichthyidae-stub