''Salvelinus inframundus'', also known as Orkney charr is a cold-water

fish Fish are aquatic, craniate, gill-bearing animals that lack limbs with digits. Included in this definition are the living hagfish, lampreys, and cartilaginous and bony fish as well as various extinct related groups. Approximately 95% of ...

in the family

Salmonidae Salmonidae is a family of ray-finned fish that constitutes the only currently extant family in the order Salmoniformes . It includes salmon (both Atlantic and Pacific species), trout (both ocean-going and landlocked), chars, freshwater whitefis ...

which 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 else ...

to Scotland.

Description

''Salvelinus inframundus'' has the following characteristics which in combination make this taxon different from other "Arctic charr" in Great Britain. It has a relatively shallow body which is less than a fifth of its body length, it has an inferiorly positioned mouth, 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 67–88% the length of its head and there are 8–9 10 soft rays in 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 ...

with 8–9 soft rays in the anal fin. It has moderately large teeth, 9–11 branchiostegals, 13–14

gill raker Gill rakers in fish are bony or cartilaginous processes that project from the branchial arch (gill arch) and are involved with suspension feeding tiny prey. They are not to be confused with the gill filaments that compose the fleshy part of the ...

s, 188–200 lateral scales and 63–64

vertebrae The spinal column, a defining synapomorphy shared by nearly all vertebrates, Hagfish are believed to have secondarily lost their spinal column is a moderately flexible series of vertebrae (singular vertebra), each constituting a characteristi ...

. Other distinguishing features cited include a blunt snout; steel-grey colour on the sides with a white to pinkish or bright orange belly; there are numerous whitish spots along the flanks, mostly on the upper half of body. The pectoral and anal fins are orange-brown to orange-red while the pelvic fins can be cherry-red, and all have a white leading edge.

Distribution

This species is known from specimens fished in Heldale Water, Hoy Island, Orkney, Scotland. It is considered

locally extinct Local extinction, also known as extirpation, refers to a species (or other taxon) of plant or animal that ceases to exist in a chosen geographic area of study, though it still exists elsewhere. Local extinctions are contrasted with global extinct ...

there since 1908 though. This rare char could be considered a

threatened Threatened species are any species (including animals, plants and fungi) which are vulnerable to endangerment in the near future. Species that are threatened are sometimes characterised by the population dynamics measure of ''critical depensa ...

species. It has been found recently in

Loch Mealt Loch Mealt is an inland fresh-water loch on the Isle of Skye in Scotland. It lies close to Ellishadder and south of Staffin, on the eastern side of the Trotternish peninsula. Geography This roughly square-shaped loch is about 1 km in le ...

, on the Isle of Skye. Since the impact of Canadian

Arctic char The Arctic char or Arctic charr (''Salvelinus alpinus'') is a cold-water fish in the family Salmonidae, native to alpine lakes and arctic and subarctic coastal waters. Its distribution is Circumpolar North. It spawns in freshwater and populat ...

fish farming upright=1.3, Salmon farming in the sea (mariculture) at Loch Ainort, Isle of Skye">mariculture.html" ;"title="Salmon farming in the sea (mariculture">Salmon farming in the sea (mariculture) at Loch Ainort, Isle of Skye, Scotland Fish farming or ...

in the loch upon the native char population is unknown and the taxonomic identity of the char deemed as ''Salvelinus inframundus'' is lacking essential information, a full

IUCN Red List The International Union for Conservation of Nature (IUCN) Red List of Threatened Species, also known as the IUCN Red List or Red Data Book, founded in 1964, is the world's most comprehensive inventory of the global conservation status of biol ...

assessment cannot be made and the species is considered data deficient.

Taxonomy

''Salevlinus inframundus'' was first formally described 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 ...

(1878–1943) in 1909 with the type locality given as Hellyal Lake, the former name of Heldale Water on the Isle of Hoy in Orkney. The specific name of this species is a compound of ''infra'' meaning "below" and ''mundus'' meaning "world" , i.e. "underworld", and is a reference to Hellyal which is derived from the Norse goddess of the underworld Hel. There is some controversy over the exact taxonomic status of the populations of charr which are found in lakes all over Europe and which show disjunct distributions and wide

phenotypic In genetics, the phenotype () is the set of observable characteristics or traits of an organism. The term covers the organism's morphology or physical form and structure, its developmental processes, its biochemical and physiological proper ...

variations. Some authorities take the view that there is a single species in Europe and that almost all populations fall within the subspecies '' Salvelinus alpinus alpinus'' and that the variations are due to non taxonomic adaptation to the local conditions. Other workers have accepted each population as a species, 15 of which have been recognised in Britain and Ireland.

References

External links

Photo of Salvelinus inframundus
{{Taxonbar, from=Q2657452 inframundus Environment of Orkney Isle of Skye Cold water fish Endemic fauna of Scotland Endemic biota of the Scottish islands Taxa named by Charles Tate Regan Fish described in 1909