The western carp gudgeon (''Hypseleotris klunzingeri'') is one of several carp gudgeon species. Carp gudgeons are very small perciform fish (similar in size, shape and colour) found in the

Australia Australia, officially the Commonwealth of Australia, is a Sovereign state, sovereign country comprising the mainland of the Australia (continent), Australian continent, the island of Tasmania, and numerous List of islands of Australia, sma ...

Murray Murray may refer to: Businesses * Murray (bicycle company), an American manufacturer of low-cost bicycles * Murrays, an Australian bus company * Murray International Trust, a Scottish investment trust * D. & W. Murray Limited, an Australian who ...

Darling River The Darling River ( Paakantyi: ''Baaka'' or ''Barka'') is the third-longest river in Australia, measuring from its source in northern New South Wales to its conflu ence with the Murray River at Wentworth, New South Wales. Including its longes ...

system, mainly in lowland environments, but some have been observed in upland environments. They are often found in small creeks, as well as billabongs and the edges of larger rivers. They prefer water 1 to 2 m deep with aquatic weed and structure provided by rocks or sunken timber (usually the latter). Like many other Murray-Darling native fish species, western carp gudgeon have crossed the

Great Dividing Range The Great Dividing Range, also known as the East Australian Cordillera or the Eastern Highlands, is a cordillera system in eastern Australia consisting of an expansive collection of mountain ranges, plateaus and rolling hills, that runs rough ...

through natural

river capture Stream capture, river capture, river piracy or stream piracy is a geomorphological phenomenon occurring when a stream or river drainage system or watershed is diverted from its own bed, and flows instead down the bed of a neighbouring stream. ...

events and are found in a number of East Coast drainages, from the Hunter River system in northern

New South Wales ) , nickname = , image_map = New South Wales in Australia.svg , map_caption = Location of New South Wales in AustraliaCoordinates: , subdivision_type = Country , subdivision_name = Australia , established_title = Before federation , es ...

to the Fitzroy River system in central

Queensland ) , nickname = Sunshine State , image_map = Queensland in Australia.svg , map_caption = Location of Queensland in Australia , subdivision_type = Country , subdivision_name = Australia , established_title = Before federation , established_ ...

Description

Western carp gudgeon are small fish, averaging 30–40 mm long, though very large specimens may approach 60 mm. Usually, their bodies are yellowish to clear with subtle, dark grey blotches, with semitranslucent fins. Males develop spectacular

spawning Spawn is the eggs and sperm released or deposited into water by aquatic animals. As a verb, ''to spawn'' refers to the process of releasing the eggs and sperm, and the act of both sexes is called spawning. Most aquatic animals, except for aquati ...

colours in summer, namely a more metallic-bronze body colour with a red stripe through the caudal (tail), anal, and spiny and soft dorsal fins. The red stripe through the anal and spiny and soft dorsal fins are topped with a tiny iridescent blue-white stripe, which are somewhat subtle on most of the fins, but are prominent and eye-catching on the spiny dorsal fin. Western carp gudgeons spawn in summer, attaching eggs to aquatic weed in the shallows. They may have suffered from small variations in river level caused by river regulation, which exposes and destroys eggs laid in shallows. They may be a critical food item for juvenile Murray cod, and likely are an important

forage fish Forage fish, also called prey fish or bait fish, are small pelagic fish which are preyed on by larger predators for food. Predators include other larger fish, seabirds and marine mammals. Typical ocean forage fish feed near the base of the food ...

for larger fish species in many waterways. Western carp gudgeons have taken to lower-altitude, man-made lakes and impoundments in the Murray-Darling system well, and are very common in some.

In aquaria

Western carp gudgeon make superb aquarium fish: they are lively, interactive, attractively coloured, and hardy. They eagerly take live or frozen

brine shrimp ''Artemia'' is a genus of aquatic crustaceans also known as brine shrimp. It is the only genus in the family Artemiidae. The first historical record of the existence of ''Artemia'' dates back to the first half of the 10th century AD from Urmia La ...

, very small

invertebrate Invertebrates are a paraphyletic group of animals that neither possess nor develop a vertebral column (commonly known as a ''backbone'' or ''spine''), derived from the notochord. This is a grouping including all animals apart from the chordate ...

s, and commercial micropellet fish feeds. Curiously, they are unavailable in aquarium stores and remain the province of keen naturalists who capture their own.

Classification

The specific name honours the

German German(s) may refer to: * Germany (of or related to) **Germania (historical use) * Germans, citizens of Germany, people of German ancestry, or native speakers of the German language ** For citizens of Germany, see also German nationality law **Ger ...

physician A physician (American English), medical practitioner (Commonwealth English), medical doctor, or simply doctor, is a health professional who practices medicine, which is concerned with promoting, maintaining or restoring health through th ...

and

zoologist Zoology ()The pronunciation of zoology as is usually regarded as nonstandard, though it is not uncommon. is the branch of biology that studies the Animal, animal kingdom, including the anatomy, structure, embryology, evolution, Biological clas ...

Carl Benjamin Klunzinger Carl Benjamin Klunzinger (18 November 1834, in Güglingen – 21 June 1914, in Stuttgart) was a German physician and zoologist. He studied medicine at the Universities of Tübingen and Würzburg, afterwards attending lectures on geology and ...

(1834-1914), who, in 1880, mistook this species for '' Eleotris cyprinoides''. Western carp gudgeon are purportedly the most common of the carp gudgeons. However, recent genetic research suggests that the carp gudgeons are a

cryptic species complex In biology, a species complex is a group of closely related organisms that are so similar in appearance and other features that the boundaries between them are often unclear. The taxa in the complex may be able to hybridize readily with each oth ...

composed of at least four species and many hybrids; their

taxonomy Taxonomy is the practice and science of categorization or classification. A taxonomy (or taxonomical classification) is a scheme of classification, especially a hierarchical classification, in which things are organized into groups or types. ...

is extremely complicated, unresolved, and not accurately reflected by current scientific and common names. Many researchers have now resorted to referring to them as simply "carp gudgeon (''Hypseleotris'' spp.)" until their taxonomy is resolved. Despite their common name, carp gudgeon are in no way related to

carp Carp are various species of oily freshwater fish from the family Cyprinidae, a very large group of fish native to Europe and Asia. While carp is consumed in many parts of the world, they are generally considered an invasive species in parts of ...

(''Cyprinus carpio'') or other members of the family

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 ...

Introduced Parasite

The introduced parasite Asian fish tapeworm '' Bothriocephalus acheilognathi'' had caused significant fish kills of the species in Canberra's

Lake Burley Griffin Lake Burley Griffin is an artificial lake in the centre of Canberra, the capital of Australia. It was completed in 1963 after the Molonglo River, which ran between the city centre and Parliamentary Triangle, was dammed. It is named after Walte ...

and is strongly suspected of affecting other Australian native freshwater fish.

Uniparental genome elimination

Most animals

reproduce sexually Sexual reproduction is a type of reproduction that involves a complex life cycle in which a gamete ( haploid reproductive cells, such as a sperm or egg cell) with a single set of chromosomes combines with another gamete to produce a zygote tha ...

, that is by a process of fusion of haploid

gamete A gamete (; , ultimately ) is a haploid cell that fuses with another haploid cell during fertilization in organisms that reproduce sexually. Gametes are an organism's reproductive cells, also referred to as sex cells. In species that produce t ...

s that arise by

meiosis Meiosis (; , since it is a reductional division) is a special type of cell division of germ cells in sexually-reproducing organisms that produces the gametes, such as sperm or egg cells. It involves two rounds of division that ultimately resu ...

in each of two different parents. Meiosis ordinarily involves

genetic recombination Genetic recombination (also known as genetic reshuffling) is the exchange of genetic material between different organisms which leads to production of offspring with combinations of traits that differ from those found in either parent. In eukaryo ...

. However, male and female hybrids of Australian carp gudgeons (''Hypseleotris'') are fertile, but practice

asexual reproduction Asexual reproduction is a type of reproduction that does not involve the fusion of gametes or change in the number of chromosomes. The offspring that arise by asexual reproduction from either unicellular or multicellular organisms inherit the fu ...

and display uniparental chromosomal elimination without genetic recombination.Majtánová Z, Dedukh D, Choleva L, Adams M, Ráb P, Unmack PJ, Ezaz T. Uniparental Genome Elimination in Australian Carp Gudgeons. Genome Biol Evol. 2021 Jun 8;13(6):evab030. doi: 10.1093/gbe/evab030. PMID: 33591327; PMCID: PMC8245195 This process is termed

hybridogenesis Parthenogenesis (; from the Greek grc, παρθένος, translit=parthénos, lit=virgin, label=none + grc, γένεσις, translit=génesis, lit=creation, label=none) is a natural form of asexual reproduction in which growth and development ...

. In these fish hybridogenesis occurs through premeiotic genome duplication of the parental genome to be transmitted, while the second parental genome appears to be gradually eliminated during development in juvenile individuals.

References

* * * Bertozzi, T., Adams, M. and Walker, K.F. (2000) Species boundaries in carp gudgeons (Eleotrididae: Hypseleotris) from the River Murray, South Australia: evidence for multiple species and extensive hybridization. ''Marine and Freshwater Research'' 51: 805–815.

External links

Native Fish Australia
{{Taxonbar, from=Q5235425

western carp gudgeon The western carp gudgeon (''Hypseleotris klunzingeri'') is one of several carp gudgeon species. Carp gudgeons are very small perciform fish (similar in size, shape and colour) found in the Australian Murray River, Murray-Darling River system, m ...

Murray-Darling basin Taxa named by James Douglas Ogilby Freshwater fish of Australia