Callichthys callichthys
Encyclopedia
The cascarudo armored catfish, bubblenest catfish, hassar, or mailed catfish is a subtropical freshwater
fish
belonging to the Callichthyinae sub-family of the Callichthyidae
family.
in 1758. It is likely to represent a species complex.
. It is very wide ranging, extending from Trinidad
to Buenos Aires
, Argentina
, including the upper Amazon River
and Paraguay River
systems.
range of 5.8 to 8.3, a water hardness of 0–30dGH
, and a temperature range of 64–83 °F (18–28 °C). When its biotype becomes dry, it can move out of the water, due to its ability to swallow air and use its intestines to absorb oxygen from the atmosphere, to find more water.
It feeds at night on fish
, insect
s, and plant
matter. Juveniles feed on rotifers, in addition to the microcrustaceans and aquatic insect larvae they find when digging into the substrate.
During reproduction, the male's belly turns orange and its pectoral spines become longer and thicker. The male builds a bubble nest
with some floating plants, fiercely guarding it after the female lays down her eggs.
, these fish attain a length of up to 14 cm (5.5 inches). It is a peaceful and relatively undemanding species, usually active in dim light or at night, but hiding when the light is bright. It is an excellent jumper and the tank should be well-covered. They require at least a 20-gallon tank, although the water should be fairly shallow (6 inches or less), especially for breeding. Part of the reason for this is their habit of gulping air from the surface. The bottom material should be fine and dark in color. Plants should be strong and well-rooted. Floating plants can be used to keep the light level down and for breeding.
A temperature range of 24°C to 26°C is adequate, although for brief periods temperatures as low as 18°C can be tolerated. The water chemistry is not critical but the water should be kept clean despite the fish's habit of stirring up the bottom.
It is easy to feed and will accept almost anything, both animal and vegetable, although it prefers live foods. Although it is primarily a bottom forager, it will include small fishes in its diet, probably taking them at night while they sleep.
Spawning has been accomplished in the aquarium and this fish is being bred commercially, although not in large quantities. Callichthys is a builder of bubblenests from plant parts, some bottom materials, and bubbles formed by a mouth secretion and air. The male forms a mass of bubbles about 20 cm (8 in.) in diameter and 10 cm (4 in) high. During the time of construction, the female is actively chased away or ignored. When the nest construction is complete, the male will accept the female. The eggs (up to several hundred) are deposited into the nest and the male or the pair will actively protect the nest for about four weeks until the fry come out of the nest at the size of 2.5 cm (1 in.).
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
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...
belonging to the Callichthyinae sub-family of the 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.
Taxonomy
It was originally described as Silurus callichthys by Carolus LinnaeusCarolus Linnaeus
Carl Linnaeus , also known after his ennoblement as , was a Swedish botanist, physician, and zoologist, who laid the foundations for the modern scheme of binomial nomenclature. He is known as the father of modern taxonomy, and is also considered one of the fathers of modern ecology...
in 1758. It is likely to represent a species complex.
Distribution
C. callichthys is distributed in all major river drainages of South AmericaSouth 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...
. It is very wide ranging, extending from 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 Buenos Aires
Buenos Aires
Buenos Aires is the capital and largest city of Argentina, and the second-largest metropolitan area in South America, after São Paulo. It is located on the western shore of the estuary of the Río de la Plata, on the southeastern coast of the South American continent...
, Argentina
Argentina
Argentina , officially the Argentine Republic , is the second largest country in South America by land area, after Brazil. It is constituted as a federation of 23 provinces and an autonomous city, Buenos Aires...
, including the upper Amazon River
Amazon River
The Amazon of South America is the second longest river in the world and by far the largest by waterflow with an average discharge greater than the next seven largest rivers combined...
and Paraguay River
Paraguay River
The Paraguay River is a major river in south central South America, running through Brazil, Bolivia, Paraguay, and Argentina...
systems.
Description
The fish will grow in length up to eight inches (20 centimeters). The females are larger and more robust, and are a dull olive-green, while the males are brighter in color, exhibiting a delicate blue or violet sheen laterally, with a more developed and longer pectoral fin spine that is reddish-brown and edged with orange or reddish-orange.Ecology
It lives in a variety of water types, from anoxic conditions (slack water zones surrounded by dense vegetation) to slightly turbid, but free-flowing, streams. It can be found in waters with 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...
range of 5.8 to 8.3, a water hardness of 0–30dGH
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...
, and a temperature range of 64–83 °F (18–28 °C). When its biotype becomes dry, it can move out of the water, due to its ability to swallow air and use its intestines to absorb oxygen from the atmosphere, to find more water.
It feeds at night on 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...
, 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
Plant
Plants are living organisms belonging to the kingdom Plantae. Precise definitions of the kingdom vary, but as the term is used here, plants include familiar organisms such as trees, flowers, herbs, bushes, grasses, vines, ferns, mosses, and green algae. The group is also called green plants or...
matter. Juveniles feed on rotifers, in addition to the microcrustaceans and aquatic insect larvae they find when digging into the substrate.
During reproduction, the male's belly turns orange and its pectoral spines become longer and thicker. The male builds a bubble nest
Bubble nest
Bubblenests, also spelled bubble nests or bubble-nests, created by some fish species, are floating masses of bubbles blown with an oral secretion, saliva bubbles, and occasionally aquatic plants, or an area for egg deposit attached at the bottom. Fish that build and guard bubble nests are known as...
with some floating plants, fiercely guarding it after the female lays down her eggs.
Relationship to humans
The cascarudo is of commercial importance in the aquarium trade industry and of minor importance as a food source. It can be kept in aquariums, with groups of more than five individuals recommended.In the aquarium
In the aquariumAquarium
An aquarium is a vivarium consisting of at least one transparent side in which water-dwelling plants or animals are kept. Fishkeepers use aquaria to keep fish, invertebrates, amphibians, marine mammals, turtles, and aquatic plants...
, these fish attain a length of up to 14 cm (5.5 inches). It is a peaceful and relatively undemanding species, usually active in dim light or at night, but hiding when the light is bright. It is an excellent jumper and the tank should be well-covered. They require at least a 20-gallon tank, although the water should be fairly shallow (6 inches or less), especially for breeding. Part of the reason for this is their habit of gulping air from the surface. The bottom material should be fine and dark in color. Plants should be strong and well-rooted. Floating plants can be used to keep the light level down and for breeding.
A temperature range of 24°C to 26°C is adequate, although for brief periods temperatures as low as 18°C can be tolerated. The water chemistry is not critical but the water should be kept clean despite the fish's habit of stirring up the bottom.
It is easy to feed and will accept almost anything, both animal and vegetable, although it prefers live foods. Although it is primarily a bottom forager, it will include small fishes in its diet, probably taking them at night while they sleep.
Spawning has been accomplished in the aquarium and this fish is being bred commercially, although not in large quantities. Callichthys is a builder of bubblenests from plant parts, some bottom materials, and bubbles formed by a mouth secretion and air. The male forms a mass of bubbles about 20 cm (8 in.) in diameter and 10 cm (4 in) high. During the time of construction, the female is actively chased away or ignored. When the nest construction is complete, the male will accept the female. The eggs (up to several hundred) are deposited into the nest and the male or the pair will actively protect the nest for about four weeks until the fry come out of the nest at the size of 2.5 cm (1 in.).