The Clanwilliam redfin (''Pseudobarbus calidus''), is a

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 ...

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 ...

in 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 ...

Cyprinidae Cyprinidae is a family of freshwater fish commonly called the carp or minnow family. It includes the carps, the true minnows, and relatives like the barbs and barbels. Cyprinidae is the largest and most diverse fish family and the largest verte ...

. It is placed with the

South Africa South Africa, officially the Republic of South Africa (RSA), is the southernmost country in Africa. It is bounded to the south by of coastline that stretch along the South Atlantic and Indian Oceans; to the north by the neighbouring countri ...

n redfins in ''

Pseudobarbus ''Pseudobarbus'' is a ray-finned fish genus in the family Cyprinidae. The type species is Burchell's redfin (''P. burchelli''). The scientific name is derived from the Ancient Greek ''pseudes'' ("false") and the Latin word ''barbus'' ("beard", ...

''. It is

tetraploid Polyploidy is a condition in which the cells of an organism have more than one pair of ( homologous) chromosomes. Most species whose cells have nuclei (eukaryotes) are diploid, meaning they have two sets of chromosomes, where each set contains ...

. Its closest living relative is probably the Twee River redfin (''P. erubescens'').de Graaf ''et al.'' (2007)

Distribution and ecology

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

Western Cape Province The Western Cape is a province of South Africa, situated on the south-western coast of the country. It is the fourth largest of the nine provinces with an area of , and the third most populous, with an estimated 7 million inhabitants in 2020 ...

, where it occurs in the upper Olifants River and its

tributaries A tributary, or affluent, is a stream or river that flows into a larger stream or main stem (or parent) river or a lake. A tributary does not flow directly into a sea or ocean. Tributaries and the main stem river drain the surrounding drainage b ...

– the Biedou, Boontjies, Boskloof, Breekkrans, Driehoeks,

Dwars DWARS, GroenLinkse Jongeren is the independent youth wing of GreenLeft, a Dutch green political party. Ideals and policies Both the ''manifest for a better world'', the organisation's program of principles and ''2025 - DWARS' proposals for the f ...

, Eselbank, Jan Dissels, Matijes, Noordhoeks, Oudste, Ratels, Rondegat,

Thee The word ''thou'' is a second-person singular pronoun in English. It is now largely archaic, having been replaced in most contexts by the word ''you'', although it remains in use in parts of Northern England and in Scots (). ''Thou'' is the ...

and

Tra Tra River Tra or TRA may refer to: Biology * TRA (gene), in humans encodes the protein T-cell receptor alpha locus * Tra (gene), in ''Drosophila melanogaster'' encodes the protein female-specific protein transformer * Tra gene, a transfer gene * Triple rele ...

s – near Clanwilliam and

Keerom Keerom may refer to * Keerom Regency, Papua Province, Indonesia * Keerom River, northern Western Papua, Papua Province, Indonesia * Keerom Dam, near Worcester, Western Cape, South Africa * Keerom Mountain, Worcester, South Africa * Keerom, farm, ...

. It inhabits the pools and shallower water in larger clear and slightly

acidic In computer science, ACID ( atomicity, consistency, isolation, durability) is a set of properties of database transactions intended to guarantee data validity despite errors, power failures, and other mishaps. In the context of databases, a sequ ...

mountain streams. They are

insectivore A robber fly eating a hoverfly An insectivore is a carnivorous animal or plant that eats insects. An alternative term is entomophage, which can also refer to the human practice of eating insects. The first vertebrate insectivores wer ...

s, eating mainly small mayflies (Baetidae), non-biting midges (Chironomidae) and

ant Ants are eusocial insects of the family Formicidae and, along with the related wasps and bees, belong to the order Hymenoptera. Ants evolved from vespoid wasp ancestors in the Cretaceous period. More than 13,800 of an estimated total of 22 ...

s (Formicidae). The breeding season is lengthy and lasts most of the summer, from November to January.

School A school is an educational institution designed to provide learning spaces and learning environments for the teaching of students under the direction of teachers. Most countries have systems of formal education, which is sometimes compuls ...

s of adults form to migrate to shallow pools with slow-moving water and

spawn Spawn or spawning may refer to: * Spawn (biology), the eggs and sperm of aquatic animals Arts, entertainment, and media * Spawn (character), a fictional character in the comic series of the same name and in the associated franchise ** '' Spawn: Ar ...

between rocks and boulders, depositing the

egg An egg is an organic vessel grown by an animal to carry a possibly fertilized egg cell (a zygote) and to incubate from it an embryo within the egg until the embryo has become an animal fetus that can survive on its own, at which point the a ...

s in crevices between these.

Status and conservation

This species is considered

Near Threatened A near-threatened species is a species which has been categorized as "Near Threatened" (NT) by the International Union for Conservation of Nature as that may be vulnerable to endangerment in the near future, but it does not currently qualify fo ...

by the

IUCN The International Union for Conservation of Nature (IUCN; officially International Union for Conservation of Nature and Natural Resources) is an international organization working in the field of nature conservation and sustainable use of natu ...

, mainly due to the adverse impact of the introduced smallmouth bass (''Micropterus dolomieu'') on its population. The most drastic declines have been in the past, and though the species is still declining it is not doing so at an alarming rate; wherever the bass has not become established yet it is actually rather plentiful.

Bluegill The bluegill (''Lepomis macrochirus''), sometimes referred to as "bream", "brim", "sunny", or "copper nose" as is common in Texas, is a species of North American freshwater fish, native to and commonly found in streams, rivers, lakes, ponds and ...

s (''Lepomis macrochirus'') and

rainbow trout The rainbow trout (''Oncorhynchus mykiss'') is a species of trout native to cold-water tributaries of the Pacific Ocean in Asia and North America. The steelhead (sometimes called "steelhead trout") is an anadromous (sea-run) form of the coasta ...

s (''Oncorhynchus mykiss'') are other

introduced species An introduced species, alien species, exotic species, adventive species, immigrant species, foreign species, non-indigenous species, or non-native species is a species living outside its native distributional range, but which has arrived there ...

that are significant as

predator Predation is a biological interaction where one organism, the predator, kills and eats another organism, its prey. It is one of a family of common feeding behaviours that includes parasitism and micropredation (which usually do not kill th ...

s of younger Clanwilliam redfins.

Banded Tilapia ''Tilapia sparrmanii'', the banded tilapia, or vlei kurper, is a widespread and adaptable cichlid fish that is found in warmer freshwater habitats of southern Africa. They prefer water with ample plant cover, and occur naturally as far north as D ...

(''Tilapia sparrmanii'') is yet another introduced fish that has an adverse effect on the stocks of ''B. calidus'', in its case due to competition for food. The other main threat is

water pollution Water pollution (or aquatic pollution) is the contamination of water bodies, usually as a result of human activities, so that it negatively affects its uses. Water bodies include lakes, rivers, oceans, aquifers, reservoirs and groundwater. Water ...

and other forms of unsustainable water use. Particularly the conversion of

riparian A riparian zone or riparian area is the interface between land and a river or stream. Riparian is also the proper nomenclature for one of the terrestrial biomes of the Earth. Plant habitats and communities along the river margins and banks ar ...

lands for

citrus ''Citrus'' is a genus of flowering plant, flowering trees and shrubs in the rue family, Rutaceae. Plants in the genus produce citrus fruits, including important crops such as Orange (fruit), oranges, Lemon, lemons, grapefruits, pomelos, and lim ...

plantation A plantation is an agricultural estate, generally centered on a plantation house, meant for farming that specializes in cash crops, usually mainly planted with a single crop, with perhaps ancillary areas for vegetables for eating and so on. The ...

s, with the resultant uninhibited

runoff Runoff, run-off or RUNOFF may refer to: * RUNOFF, the first computer text-formatting program * Runoff or run-off, another name for bleed, printing that lies beyond the edges to which a printed sheet is trimmed * Runoff or run-off, a stock market ...

pesticide Pesticides are substances that are meant to control pests. This includes herbicide, insecticide, nematicide, molluscicide, piscicide, avicide, rodenticide, bactericide, insect repellent, animal repellent, microbicide, fungicide, and lampri ...

s and

fertilizer A fertilizer (American English) or fertiliser (British English; see spelling differences) is any material of natural or synthetic origin that is applied to soil or to plant tissues to supply plant nutrients. Fertilizers may be distinct from ...

s, is considered very harmful. The Clanwilliam redfin occurs in the

Cederberg Wilderness Area The Cederberg mountains are located near Clanwilliam, approximately 300 km north of Cape Town, South Africa at about . The mountain range is named after the endangered Clanwilliam cedar (''Widdringtonia wallichii''), which is a tree end ...

and the Matjies River Nature Reserve, where it is at least safe from

habitat destruction Habitat destruction (also termed habitat loss and habitat reduction) is the process by which a natural habitat becomes incapable of supporting its native species. The organisms that previously inhabited the site are displaced or dead, thereby ...

. It is listed as Endangered by the Nature Conservation Ordinance of

. For the time being, it may not be killed or caught. The species is on display in public aquaria of

Cape Town Cape Town ( af, Kaapstad; , xh, iKapa) is one of South Africa's three capital cities, serving as the seat of the Parliament of South Africa. It is the legislative capital of the country, the oldest city in the country, and the second largest ...

, Clanwilliam and Jonkershoek to educate the public on its

conservation Conservation is the preservation or efficient use of resources, or the conservation of various quantities under physical laws. Conservation may also refer to: Environment and natural resources * Nature conservation, the protection and manageme ...

needs.

References

* (2007): Evolutionary origin of Lake Tana's (Ethiopia) small ''Barbus'' species: indications of rapid ecological divergence and speciation. '' Anim. Biol.'' 57(1): 39-48. (HTML abstract) * {{Taxonbar, from=Q302374 Pseudobarbus Freshwater fish of South Africa Fish described in 1938 Taxa named by Keppel Harcourt Barnard Taxonomy articles created by Polbot