Bronze corydoras
Encyclopedia
The bronze corydoras green corydoras, bronze catfish, lightspot corydoras or wavy catfish is a tropical freshwater
fish in the "armored catfish" (Callichthyidae
) family. It is widely distributed in South America
on the eastern side of the Andes
, from Colombia
and Trinidad
to the Río de la Plata
basin. They were originally described as Hoplosoma aeneum by Theodore Gill
in 1858 and have also been referred to as Callichthys aeneus.
is 10 years. It has a yellow or pink body, white belly, and is blue-grey over its head and back. Its fins are yellow or pink and immaculate. In common with most Corydoras the dorsal, pectoral and adipose fins have an additional sharp barb and have a mild poison which causes fish which try to attack them to get stung. A brownish-orange patch is usually present on the head, just before the dorsal fin, and is its most distinctive feature when viewed from above in the stream. Their upper sides are often a greenish color, which is the reason another common name for this fish is the green corydoras.
Like many other catfishes, females are larger than males in this species.
6.0-8.0, and hardness
5 to 19 DGH
. Like most members of the Corydoras genus, these catfish
have a unique method of coping with the low oxygen
content that prevails in such environments. In addition to utilizing their gills like any other fish
, they rapidly come to the surface of the water and draw air in through their mouth. This air is then absorbed through the wall of the intestine and any surplus air is expelled through the vent
. It typically stays in schools
of 20 to 30 individuals. It feeds on worm
s, benthic crustacean
s, insect
s, and plant matter.
Bronze cories have a unique method of insemination. When these fish reproduce, the male will present his abdomen to the female. The female will attach her mouth to the male's genital opening, creating the well-known "T-position" many Corydoras exhibit during courtship. The female will then drink the sperm
. The sperm rapidly moves through her intestines and is discharged together with her eggs into a pouch formed by her pelvic fins. The female can then swim away and deposit the pouch somewhere else alone. Because the T-position is exhibited in other species than just C. aeneus, it is likely that they also exhibit this behavior. In the wild, eggs are laid on waterweeds.
Males do not form territories or compete over females; interference between males might only happen when two males present their abdomens simultaneously. On the other hand, females do not choose between males. Mating is more or less random; therefore, male reproductive success is directly related to courtship frequency.
The eggs of C. aeneus exhibit a unique surface pattern with small villi
-like protuberances which resemble attaching-filaments of teleost eggs. These structures allow the eggs to be adhesive and stick to a specific place or to each other. The presence of these structures may be related to the turbid habitat in which this species lives.
, Europe, and Singapore
. Most of the available fish are therefore domestic strains. Wild imports are reported to be less easy to breed.
They are a hardy and useful aquarium fish despite having a coloration that is by no means striking or unusual. Many aquarists are fascinated by the habits of these fish. They ceaselessly comb the bottom of the aquarium for food and therefore disturb it slightly, sending up detritus
and waste material that has settled loosely on the bottom. They prefer being kept in groups
of 5 or more, being sociable fish and are ideal fish for a community tank
. Other Corydoras
species can be placed in the same aquarium, and despite the strong resemblance many species bear to one another, the species will tend to separate out and only move about among their own kind.
Corydoras aeneus is not particular about the composition of the water. Adequate conditions are a temperature range of 20 to 28 °C (68 to 82 °F), pH of 6.0-8.0, and hardness of 2–30 DGH
. The water should have no salt added to it. A fairly dense growth of plants with a number of possible hiding places is greatly appreciated. Corys are easy to feed, they are omnivore
s eating all flake and pelleted food and also live and frozen foods. When it comes to sperm, then the female glues the eggs, only a few in number, to the chosen substrate and then (sometimes) quickly touches them with her mouth. After several acts of spawning, which span a total of two to three hours, one female will have produced up to 200 eggs. Frequently, two males are used for each female, as one male has difficulty fertilizing all the eggs. The eggs gradually grow darker in color, and just prior to hatching (ranging from three days at 28 °C to a week at 20 °C) they turn dark brown. The fry keep to the bottom of the tank, feeding on detritus and any fine foods available. The parents may spawn again within two to three weeks.
" or "juicing" fish.
Freshwater
Fresh water is naturally occurring water on the Earth's surface in ice sheets, ice caps, glaciers, bogs, ponds, lakes, rivers and streams, and underground as groundwater in aquifers and underground streams. Fresh water is generally characterized by having low concentrations of dissolved salts and...
fish in the "armored catfish" (Callichthyidae
Callichthyidae
Callichthyidae is a family of catfishes , called armored catfishes due to the two rows of bony plates running down the length of the body. This family contains some of the most popular freshwater aquarium fish, such as the Corydoras.-Taxonomy:The family derives its name from the Greek words kallis...
) family. It is widely distributed in South America
South America
South America is a continent situated in the Western Hemisphere, mostly in the Southern Hemisphere, with a relatively small portion in the Northern Hemisphere. The continent is also considered a subcontinent of the Americas. It is bordered on the west by the Pacific Ocean and on the north and east...
on the eastern side of the Andes
Andes
The Andes is the world's longest continental mountain range. It is a continual range of highlands along the western coast of South America. This range is about long, about to wide , and of an average height of about .Along its length, the Andes is split into several ranges, which are separated...
, from Colombia
Colombia
Colombia, officially the Republic of Colombia , is a unitary constitutional republic comprising thirty-two departments. The country is located in northwestern South America, bordered to the east by Venezuela and Brazil; to the south by Ecuador and Peru; to the north by the Caribbean Sea; to the...
and Trinidad
Trinidad
Trinidad is the larger and more populous of the two major islands and numerous landforms which make up the island nation of Trinidad and Tobago. It is the southernmost island in the Caribbean and lies just off the northeastern coast of Venezuela. With an area of it is also the fifth largest in...
to the Río de la Plata
Río de la Plata
The Río de la Plata —sometimes rendered River Plate in British English and the Commonwealth, and occasionally rendered [La] Plata River in other English-speaking countries—is the river and estuary formed by the confluence of the Uruguay River and the Paraná River on the border between Argentina and...
basin. They were originally described as Hoplosoma aeneum by Theodore Gill
Theodore Gill
Theodore Nicholas Gill was an American ichthyologist, mammalogist, malacologist and librarian.Born and educated in New York City under private tutors, Gill early showed interest in natural history. He was associated with J...
in 1858 and have also been referred to as Callichthys aeneus.
Appearance and anatomy
The adult size is 6½ cm for males and a slightly larger 7 cm for females (2½ to 2¾ inches). Their average life spanLife expectancy
Life expectancy is the expected number of years of life remaining at a given age. It is denoted by ex, which means the average number of subsequent years of life for someone now aged x, according to a particular mortality experience...
is 10 years. It has a yellow or pink body, white belly, and is blue-grey over its head and back. Its fins are yellow or pink and immaculate. In common with most Corydoras the dorsal, pectoral and adipose fins have an additional sharp barb and have a mild poison which causes fish which try to attack them to get stung. A brownish-orange patch is usually present on the head, just before the dorsal fin, and is its most distinctive feature when viewed from above in the stream. Their upper sides are often a greenish color, which is the reason another common name for this fish is the green corydoras.
Like many other catfishes, females are larger than males in this species.
Ecology
They are found in quiet, shallow waters with soft bottoms that can sometimes be heavily polluted by clouds of disturbed mud from the bottom, but it also inhabits running waters. In its native habitat, it inhabits waters with a temperature range of 25 °C to 28 °C (77 °F to 82 °F), pHPH
In chemistry, pH is a measure of the acidity or basicity of an aqueous solution. Pure water is said to be neutral, with a pH close to 7.0 at . Solutions with a pH less than 7 are said to be acidic and solutions with a pH greater than 7 are basic or alkaline...
6.0-8.0, and hardness
Hard water
Hard water is water that has high mineral content . Hard water has high concentrations of Ca2+ and Mg2+ ions. Hard water is generally not harmful to one's health but can pose serious problems in industrial settings, where water hardness is monitored to avoid costly breakdowns in boilers, cooling...
5 to 19 DGH
DGH
Degrees of general hardness is a unit of water hardness, specifically of general hardness.General hardness is a measure of the concentration of metal divalent ions such as calcium and magnesium per volume of water...
. Like most members of the Corydoras genus, these catfish
Catfish
Catfishes are a diverse group of ray-finned fish. Named for their prominent barbels, which resemble a cat's whiskers, catfish range in size and behavior from the heaviest and longest, the Mekong giant catfish from Southeast Asia and the second longest, the wels catfish of Eurasia, to detritivores...
have a unique method of coping with the low oxygen
Oxygen
Oxygen is the element with atomic number 8 and represented by the symbol O. Its name derives from the Greek roots ὀξύς and -γενής , because at the time of naming, it was mistakenly thought that all acids required oxygen in their composition...
content that prevails in such environments. In addition to utilizing their gills like any other fish
Fish
Fish are a paraphyletic group of organisms that consist of all gill-bearing aquatic vertebrate 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...
, they rapidly come to the surface of the water and draw air in through their mouth. This air is then absorbed through the wall of the intestine and any surplus air is expelled through the vent
Fish anatomy
Fish anatomy is primarily governed by the physical characteristics of water, which is much denser than air, holds a relatively small amount of dissolved oxygen, and absorbs more light than air does.- Body :...
. It typically stays in schools
Shoaling and schooling
In biology, any group of fish that stay together for social reasons are said to be shoaling , and if, in addition, the group is swimming in the same direction in a coordinated manner, they are said to be schooling . In common usage, the terms are sometimes used rather loosely...
of 20 to 30 individuals. It feeds on worm
Worm
The term worm refers to an obsolete taxon used by Carolus Linnaeus and Jean-Baptiste Lamarck for all non-arthropod invertebrate animals, and stems from the Old English word wyrm. Currently it is used to describe many different distantly-related animals that typically have a long cylindrical...
s, benthic crustacean
Crustacean
Crustaceans form a very large group of arthropods, usually treated as a subphylum, which includes such familiar animals as crabs, lobsters, crayfish, shrimp, krill and barnacles. The 50,000 described species range in size from Stygotantulus stocki at , to the Japanese spider crab with a leg span...
s, insect
Insect
Insects are a class of living creatures within the arthropods that have a chitinous exoskeleton, a three-part body , three pairs of jointed legs, compound eyes, and two antennae...
s, and plant matter.
Reproduction
Reproduction occurs with the onset of the rainy season, which changes the water chemistry. Females spawn 10–20 egg-clutches with multiple males at a time, but an entire egg clutch is inseminated by sperm of a single male.Bronze cories have a unique method of insemination. When these fish reproduce, the male will present his abdomen to the female. The female will attach her mouth to the male's genital opening, creating the well-known "T-position" many Corydoras exhibit during courtship. The female will then drink the sperm
Sperm
The term sperm is derived from the Greek word sperma and refers to the male reproductive cells. In the types of sexual reproduction known as anisogamy and oogamy, there is a marked difference in the size of the gametes with the smaller one being termed the "male" or sperm cell...
. The sperm rapidly moves through her intestines and is discharged together with her eggs into a pouch formed by her pelvic fins. The female can then swim away and deposit the pouch somewhere else alone. Because the T-position is exhibited in other species than just C. aeneus, it is likely that they also exhibit this behavior. In the wild, eggs are laid on waterweeds.
Males do not form territories or compete over females; interference between males might only happen when two males present their abdomens simultaneously. On the other hand, females do not choose between males. Mating is more or less random; therefore, male reproductive success is directly related to courtship frequency.
The eggs of C. aeneus exhibit a unique surface pattern with small villi
Villus
Intestinal villi are tiny, finger-like projections that protrude from the epithelial lining of the intestinal wall. Each villus is approximately 0.5-1.6 mm in length and has many microvilli , each of which are much smaller than a single villus...
-like protuberances which resemble attaching-filaments of teleost eggs. These structures allow the eggs to be adhesive and stick to a specific place or to each other. The presence of these structures may be related to the turbid habitat in which this species lives.
In the aquarium
Bronze corys are probably the most popular Corydoras species. It is annually bred and shipped in large quantities all over the world It is easily bred and is produced in commercial quantities in the United StatesUnited States
The United States of America is a federal constitutional republic comprising fifty states and a federal district...
, Europe, and Singapore
Singapore
Singapore , officially the Republic of Singapore, is a Southeast Asian city-state off the southern tip of the Malay Peninsula, north of the equator. An island country made up of 63 islands, it is separated from Malaysia by the Straits of Johor to its north and from Indonesia's Riau Islands by the...
. Most of the available fish are therefore domestic strains. Wild imports are reported to be less easy to breed.
They are a hardy and useful aquarium fish despite having a coloration that is by no means striking or unusual. Many aquarists are fascinated by the habits of these fish. They ceaselessly comb the bottom of the aquarium for food and therefore disturb it slightly, sending up detritus
Detritus
Detritus is a biological term used to describe dead or waste organic material.Detritus may also refer to:* Detritus , a geological term used to describe the particles of rock produced by weathering...
and waste material that has settled loosely on the bottom. They prefer being kept in groups
Swarm
Swarm behaviour, or swarming, is a collective behaviour exhibited by animals of similar size which aggregate together, perhaps milling about the same spot or perhaps moving en masse or migrating in some direction. As a term, swarming is applied particularly to insects, but can also be applied to...
of 5 or more, being sociable fish and are ideal fish for a community tank
Community tank
Community aquaria are tanks that are designed to contain more than one species of fish. Most commonly they include a variety of species that do not normally occur together in nature, for example angelfish from Brazil, swordtails from Mexico, and gouramis from South East Asia...
. Other Corydoras
Corydoras
Members of the South American Corydoras genus are freshwater temperate and tropical catfish in the armored catfish family , and are commonly referred to as corydorases, cories, or cory catfish.-Taxonomy:...
species can be placed in the same aquarium, and despite the strong resemblance many species bear to one another, the species will tend to separate out and only move about among their own kind.
Corydoras aeneus is not particular about the composition of the water. Adequate conditions are a temperature range of 20 to 28 °C (68 to 82 °F), pH of 6.0-8.0, and hardness of 2–30 DGH
DGH
Degrees of general hardness is a unit of water hardness, specifically of general hardness.General hardness is a measure of the concentration of metal divalent ions such as calcium and magnesium per volume of water...
. The water should have no salt added to it. A fairly dense growth of plants with a number of possible hiding places is greatly appreciated. Corys are easy to feed, they are omnivore
Omnivore
Omnivores are species that eat both plants and animals as their primary food source...
s eating all flake and pelleted food and also live and frozen foods. When it comes to sperm, then the female glues the eggs, only a few in number, to the chosen substrate and then (sometimes) quickly touches them with her mouth. After several acts of spawning, which span a total of two to three hours, one female will have produced up to 200 eggs. Frequently, two males are used for each female, as one male has difficulty fertilizing all the eggs. The eggs gradually grow darker in color, and just prior to hatching (ranging from three days at 28 °C to a week at 20 °C) they turn dark brown. The fry keep to the bottom of the tank, feeding on detritus and any fine foods available. The parents may spawn again within two to three weeks.
Albino corydoras
The albino variety is an albino variety of the bronze corydoras that has been developed for the aquarium trade, with a pale pink or orange body and red eyes. It is physically similar to normally-colored individuals, although some breeders report that the fry are a little slower to develop. Others say that the albinos are practically blind and that the males are somewhat sterile, although this may be due to extensive inbreeding. Albino bronze corys are frequently injected with bright dye (via a needle) and sold in aquariums. This controversial practice is known as "paintingPainted fish
The term painted fish refers to ornamental aquarium fish which have been artificially coloured to appeal to consumers. This artificial colouring, also known as juicing, is achieved by a number of methods, such as injecting the fish with a hypodermic syringe containing bright fluorescent colour dye,...
" or "juicing" fish.