''Chirostoma'' is a genus of

Neotropical silversides The Neotropical silversides are a family, Atherinopsidae, of fishes in the order Atheriniformes. About 112 species in 13 genera are distributed throughout the tropical and temperate waters of the New World, including both marine and freshwa ...

from the

Lerma River The Lerma River ( es, Río Lerma) is Mexico's second longest river. It is a river in west-central Mexico that begins in Mexican Plateau at an altitude over above sea level, and ends where it empties into Lake Chapala, Mexico's largest lake, nea ...

basin in

Mexico Mexico ( Spanish: México), officially the United Mexican States, is a country in the southern portion of North America. It is bordered to the north by the United States; to the south and west by the Pacific Ocean; to the southeast by Guate ...

, including lakes

Chapala Chapala may refer to: * Chapala, Jalisco, a town in the Mexican state of Jalisco, on the northern shore of Lake Chapala * Lake Chapala, the largest freshwater lake in Mexico, in the states of Jalisco and Michoacán * ''Chapala'', a 1899 painting ...

and

Pátzcuaro Pátzcuaro () is a city and municipality located in the state of Michoacán. The town was founded sometime in the 1320s, at first becoming the capital of the Purépecha Empire and later its ceremonial center. After the Spanish took over, Vasco ...

. Fish in the genus collectively go by the common name charal/charales in their native range (a name also used for the related '' Poblana''). They are heavily fished, but several of the species have become

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 ...

due to habitat loss (pollution, water extraction and drought),

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 the ...

and

overfishing Overfishing is the removal of a species of fish (i.e. fishing) from a body of water at a rate greater than that the species can replenish its population naturally (i.e. the overexploitation of the fishery's existing fish stock), resulting in the ...

. Three species are considered extinct: '' C. bartoni'' (disappeared 2006), '' C. charari'' (1957) and '' C. compressum'' (1900). Four others have not been recorded recently and may also be extinct.

Appearance and behavior

''Chirostoma'' are generally silvery-white, pale gray-brown or dull yellowish in color, and have a long horizontal line on the side of the body (inconspicuous and more spotty in some species). They vary in size, ranging from species that are less than long to species that can surpass . Despite the differences, there is great overlap in the food choice of these

filter feeder Filter feeders are a sub-group of suspension feeding animals that feed by straining suspended matter and food particles from water, typically by passing the water over a specialized filtering structure. Some animals that use this method of feedin ...

s with the main diet being composed of various small organisms (mostly

plankton Plankton are the diverse collection of organisms found in water (or air) that are unable to propel themselves against a current (or wind). The individual organisms constituting plankton are called plankters. In the ocean, they provide a cr ...

ic) such as

copepod Copepods (; meaning "oar-feet") are a group of small crustaceans found in nearly every freshwater and saltwater habitat. Some species are planktonic (inhabiting sea waters), some are benthic (living on the ocean floor), a number of species have p ...

cladocera The Diplostraca or Cladocera, commonly known as water fleas, are a superorder of small crustaceans that feed on microscopic chunks of organic matter (excluding some predatory forms). Over 1000 species have been recognised so far, with many more ...

ns,

rotifer The rotifers (, from the Latin , "wheel", and , "bearing"), commonly called wheel animals or wheel animalcules, make up a phylum (Rotifera ) of microscopic and near-microscopic pseudocoelomate animals. They were first described by Rev. John H ...

s, amphipods,

oligochaete Oligochaeta () is a subclass of animals in the phylum Annelida, which is made up of many types of aquatic and terrestrial worms, including all of the various earthworms. Specifically, oligochaetes comprise the terrestrial megadrile earthworm ...

s, nematodes, insect larvae, and fish eggs and embryos (including those of silversides). They are

ovoviviparous Ovoviviparity, ovovivipary, ovivipary, or aplacental viviparity is a term used as a "bridging" form of reproduction between egg-laying oviparous and live-bearing viviparous reproduction. Ovoviviparous animals possess embryos that develop insi ...

and employ

external fertilization External fertilization is a mode of reproduction in which a male organism's sperm fertilizes a female organism's egg outside of the female's body. It is contrasted with internal fertilization, in which sperm are introduced via insemination and the ...

. During spawning each female lays a few hundred to a few thousand eggs.

Species

There are currently 23 recognized species in this genus. Additionally, the 4 '' Poblana'' species are sometimes included in ''Chirostoma'' instead of being placed in a separate genus. Several species of ''Chirostoma'' can

hybridize Hybridization (or hybridisation) may refer to: * Hybridization (biology), the process of combining different varieties of organisms to create a hybrid * Orbital hybridization, in chemistry, the mixing of atomic orbitals into new hybrid orbitals * ...

. * '' Chirostoma aculeatum'' C. D. Barbour, 1973 (Scowling silverside) * '' Chirostoma arge'' ( D. S. Jordan & Snyder, 1899) (Largetooth silverside) * ''

Chirostoma attenuatum ''Chirostoma attenuatum'' – also known as slender silverside – was featured in the 2009 IUCN Red List of Threatened Species and the American Fisheries Society. They are found in Patzcuaro, Central Mexico. The species In biology, a spec ...

'' Meek, 1902 (Slender silverside) * †'' Chirostoma bartoni'' D. S. Jordan & Evermann, 1896 (Alberca silverside) * ''

Chirostoma chapalae ''Chirostoma'' is a genus of Neotropical silversides from the Lerma River basin in Mexico, including lakes Chapala and Pátzcuaro. Fish in the genus collectively go by the common name charal/charales in their native range (a name also used f ...

'' D. S. Jordan & Snyder, 1899 (Smallmouth silverside) * †''

Chirostoma charari ''Chirostoma charari'', the least silverside, is a species of neotropical silverside endemic to Mexico. This species has only been found in a spring in the Lake Cuitzeo basin on the Mesa Central of the Mexican Plateau The Central Mexican Plate ...

'' ( F. de Buen, 1945) (Least silverside) * †'' Chirostoma compressum'' F. de Buen, 1940 * '' Chirostoma consocium'' D. S. Jordan & C. L. Hubbs, 1919 (Ranch silverside) * ''

Chirostoma contrerasi ''Chirostoma'' is a genus of Neotropical silversides from the Lerma River basin in Mexico, including lakes Chapala and Pátzcuaro. Fish in the genus collectively go by the common name charal/charales in their native range (a name also used for ...

'' C. D. Barbour, 2002 (Ajijic silverside) * ''

Chirostoma copandaro ''Chirostoma'' is a genus of Neotropical silversides from the Lerma River basin in Mexico, including lakes Chapala and Pátzcuaro. Fish in the genus collectively go by the common name charal/charales in their native range (a name also used for ...

'' F. de Buen, 1945 * ''

Chirostoma estor ''Chirostoma'' is a genus of Neotropical silversides from the Lerma River basin in Mexico, including lakes Chapala and Pátzcuaro. Fish in the genus collectively go by the common name charal/charales in their native range (a name also used for ...

'' D. S. Jordan, 1880 (Pike silverside) * ''

Chirostoma grandocule ''Chirostoma'' is a genus of Neotropical silversides from the Lerma River basin in Mexico, including lakes Chapala and Pátzcuaro. Fish in the genus collectively go by the common name charal/charales in their native range (a name also used f ...

'' ( Steindachner, 1894) (Bigeye silverside) * ''

Chirostoma humboldtianum ''Chirostoma humboldtianum'', the shortfin silverside, is a species of neotropical silverside endemic to Mexico. It reaches a maximum length of around 20 cm. This species was described as ''Atherina humboldtiana'' by Achille Valenciennes in ...

'' (

Valenciennes Valenciennes (, also , , ; nl, label=also Dutch, Valencijn; pcd, Valincyinnes or ; la, Valentianae) is a commune in the Nord department, Hauts-de-France, France. It lies on the Scheldt () river. Although the city and region experienced a ...

, 1835) (Shortfin silverside) * ''

Chirostoma jordani ''Chirostoma'' is a genus of Neotropical silversides from the Lerma River basin in Mexico, including lakes Chapala and Pátzcuaro. Fish in the genus collectively go by the common name charal/charales in their native range (a name also used for ...

'' Woolman, 1894 (Charal) * ''

Chirostoma labarcae ''Chirostoma'' is a genus of Neotropical silversides from the Lerma River basin in Mexico, including lakes Chapala and Pátzcuaro. Fish in the genus collectively go by the common name charal/charales in their native range (a name also used for ...

'' Meek, 1902 (Sharpnose silverside) * ''

Chirostoma lucius ''Chirostoma'' is a genus of Neotropical silversides from the Lerma River basin in Mexico, including lakes Chapala and Pátzcuaro. Fish in the genus collectively go by the common name charal/charales in their native range (a name also used f ...

'' Boulenger, 1900 (Longjaw silverside) * ''

Chirostoma melanoccus ''Chirostoma'' is a genus of Neotropical silversides from the Lerma River basin in Mexico, including lakes Chapala and Pátzcuaro. Fish in the genus collectively go by the common name charal/charales in their native range (a name also used f ...

Álvarez Álvarez or Álvares may refer to: People * Álvarez (surname), Spanish surname Places * Alvares (river), a river in northern Spain * Alvares (ski resort), in Iran * Alvares, Iran * Alvares, Portugal * Álvarez, Santa Fe, a town in the province o ...

, 1963 (Blunthead silverside) * '' Chirostoma patzcuaro'' Meek, 1902 (Patzcuaro silverside) * ''

Chirostoma promelas ''Chirostoma'' is a genus of Neotropical silversides from the Lerma River basin in Mexico, including lakes Chapala and Pátzcuaro. Fish in the genus collectively go by the common name charal/charales in their native range (a name also used for ...

'' D. S. Jordan & Snyder, 1899 (Blacknose silverside) * ''

Chirostoma reseratum ''Chirostoma'' is a genus of Neotropical silversides from the Lerma River basin in Mexico, including lakes Lake Chapala, Chapala and Lake Pátzcuaro, Pátzcuaro. Fish in the genus collectively go by the common name charal/charales in their nativ ...

, 1963 * '' Chirostoma riojai'' Solórzano & Y. López, 1966 (Toluca silverside) * ''

Chirostoma sphyraena ''Chirostoma'' is a genus of Neotropical silversides from the Lerma River basin in Mexico, including lakes Chapala and Pátzcuaro. Fish in the genus collectively go by the common name charal/charales in their native range (a name also used f ...

'' Boulenger, 1900 (Bigmouth silverside) * ''

Chirostoma zirahuen ''Chirostoma'' is a genus of Neotropical silversides from the Lerma River basin in Mexico, including lakes Chapala and Pátzcuaro. Fish in the genus collectively go by the common name charal/charales in their native range (a name also used for ...

'' Meek, 1902

Culinary use

Dried ''Chirostoma'' can be fried with salt and lemon and covered with fried egg with garlic or chili. They can be added to omelettes or fried pancakes in

green sauce Green sauce or greensauce is a family of cold, uncooked sauces based on chopped herbs, including the Spanish and Italian ''salsa verde'', the French ''sauce verte'', the German ''Grüne Soße'' or ''Frankfurter Grie Soß'' (Frankfurt dialect) ...

Availability

''Chirostoma'' can be purchased at restaurants on the shores of

Lake Chapala Lake Chapala ( es, Lago de Chapala, ) is Mexico's largest freshwater lake. It lies in the municipalities of Ocotlán, Chapala, Jocotepec, Poncitlán, and Jamay, in Jalisco, and in Venustiano Carranza and Cojumatlán de Régules, in Michoac ...

in local markets. They are typically sold dried and are affordable. '' C. estor'' is

aquaculture Aquaculture (less commonly spelled aquiculture), also known as aquafarming, is the controlled cultivation ("farming") of aquatic organisms such as fish, crustaceans, mollusks, algae and other organisms of value such as aquatic plants (e.g. lotus ...

d, and '' C. humboldtianum'', another potential candidate for aquaculture, has been bred in captivity.

References

{{Taxonbar, from=Q2055925 Atherinopsidae Extant Pliocene first appearances Taxonomy articles created by Polbot Fish of Mexico Mexican cuisine