''Rhodeus'' is a genus of

cyprinid 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 ...

fish Fish are Aquatic animal, aquatic, craniate, gill-bearing animals that lack Limb (anatomy), limbs with Digit (anatomy), digits. Included in this definition are the living hagfish, lampreys, and Chondrichthyes, cartilaginous and bony fish as we ...

, consisting of 23 species called bitterlings. The

scientific name In taxonomy, binomial nomenclature ("two-term naming system"), also called nomenclature ("two-name naming system") or binary nomenclature, is a formal system of naming species of living things by giving each a name composed of two parts, bo ...

is derived from the Greek word ', meaning "

rose A rose is either a woody perennial flowering plant of the genus ''Rosa'' (), in the family Rosaceae (), or the flower it bears. There are over three hundred species and tens of thousands of cultivars. They form a group of plants that can be ...

". Most species in the genus are restricted to Asia, but two species are found in Europe (''R. amarus'' and ''R. meridionalis''). Bitterlings are short-lived species, generally surviving only about five years. Their maximum size is 11 cm, but they are usually much shorter. Bitterlings inhabit slow-flowing or still waters, such as ponds, lakes, marshes, muddy and sandy pools, and river backwaters. Because they depend on freshwater mussels to reproduce, their range is restricted. Bitterlings are omnivorous, feeding on both invertebrates and plants. Bitterlings have a remarkable reproduction strategy where parents transfer responsibility for the care of their young to various species of freshwater mussels ( Unionidae and

Margaritiferidae Margaritiferidae is a family of medium-sized freshwater mussels, aquatic bivalve molluscs in the order Unionida. Text may have been copied from this source, which is available under Attribution 4.0 International (CC BY 4.0)licence. It is the ...

). The female extends her long

ovipositor The ovipositor is a tube-like organ used by some animals, especially insects, for the laying of eggs. In insects, an ovipositor consists of a maximum of three pairs of appendages. The details and morphology of the ovipositor vary, but typical ...

into the mantle cavity of the mussel and deposits her eggs between the gill filaments. The male then ejects his sperm into the mussel's inhalent water current and fertilization takes place within the gills of the host. The same female may use a number of mussels, and she deposits only one or two yellow, oval eggs into each. Early developmental stages are protected from predation within the body of the mussel. After 3 to 4 weeks, larvae swim away from the hosts to continue life on their own. In 1936, the bitterling was thought to respond to hormones in a pregnant woman's urine, but the work was later discredited.

Species

This genus and '' Acheilognathus'' have a convoluted taxonomic history, one being at times included in the other. They are now considered separate, but some species formerly in ''Rhodeus'' are now in ''Acheilognathus''. There are currently 23 recognized species in this genus: *'' Rhodeus albomarginatus'' F. Li & R. Arai, 2014 *''

Rhodeus amarus The European bitterling (''Rhodeus amarus'') is a temperate freshwater fish belonging to the subfamily Acheilognathinae of the family Cyprinidae. It originates in Europe, ranging from the Rhone River basin in France to the Neva River in Russia. I ...

Bloch Bloch is a surname of German origin. Notable people with this surname include: A–F * (1859-1914), French rabbi *Adele Bloch-Bauer (1881-1925), Austrian entrepreneur * Albert Bloch (1882–1961), American painter * (born 1972), German motor journa ...

, 1782 (European bitterling) *'' Rhodeus amurensis'' Vronsky, 1967 *'' Rhodeus atremius'' D. S. Jordan & W. F. Thompson, 1914 (Kyushu bitterling) *'' Rhodeus colchicus'' Bogutskaya & Komlev, 2001 (Georgian bitterling) *'' Rhodeus cyanorostris'' *'' Rhodeus fangi'' C. P. Miao, 1934 *'' Rhodeus haradai'' R. Arai, N. Suzuki & S. C. Shen, 1990 *'' Rhodeus laoensis''

Kottelat Maurice Kottelat (born 16 July 1957 in Delémont, SwitzerlandCo ...

, A. Doi & Musikasinthorn, 1998 *''

Rhodeus meridionalis ''Rhodeus meridionalis'' is a species of freshwater ray-finned fish in the genus ''Rhodeus''. It is found in Bulgaria, Greece, North Macedonia, and Serbia, where it is found from the Vardar River The Vardar (; mk, , , ) or Axios () is the ...

'' S. L. Karaman, 1924 *'' Rhodeus monguonensis'' G. L. Li, 1989 *''

Rhodeus ocellatus The rosy bitterling or Tairiku baratanago (''Rhodeus ocellatus'') is a small freshwater fish belonging to the family Cyprinidae (carp), native to East Asia from the Amur River basin to the Pearl River basin. Females are about long and males are ...

'' Kner, 1866 (rosy bitterling) *'' Rhodeus nigrodorsalis'' *'' Rhodeus pseudosericeus'' R. Arai, S. R. Jeon & Ueda, 2001 *'' Rhodeus rheinardti'' Tirant, 1883 *'' Rhodeus sciosemus'' D. S. Jordan & W. F. Thompson, 1914 *'' Rhodeus sericeus'' Pallas, 1776 (Amur bitterling) *''

Rhodeus shitaiensis ''Rhodeus shitaiensis'' is a species of freshwater ray-finned fish in the genus ''Rhodeus''. It is endemic to China, where it is found in the Qiupu River of the Yangtze The Yangtze or Yangzi ( or ; ) is the longest river in Asia, ...

'' F. Li & R. Arai, 2011 *'' Rhodeus sinensis'' Günther, 1868 (Light's bitterling) *''

Rhodeus smithii ''Rhodeus smithii'', sometimes known as the Japanese rosy bitterling, Japanese bitterling, or Nippon baratanago is a temperate freshwater fish belonging to the Acheilognathinae subfamily of the family Cyprinidae. It originates in stagnant water ...

Regan The family name Regan, along with its cognates O'Regan, O Regan, Reagan, and O'Reagan, is an Anglicized form of the Irish surname Ó Riagáin or Ó Ríogáin, from Ua Riagáin. The meaning is likely to have originated in ancient Gaelic ''ri'' ...

, 1908 *'' Rhodeus spinalis'' Ōshima, 1926 *''

Rhodeus suigensis ''Rhodeus suigensis'' is a temperate freshwater fish belonging to the Acheilognathinae subfamily of the family Cyprinidae. It originated in inland rivers in Japan and the Korean peninsula. It was originally described as ''Pseudoperilampus suigen ...

'' T. Mori, 1935 *'' Rhodeus uyekii'' T. Mori, 1935

Species

References

Further reading