Turquoise akara - this term today unites several species of cichlids, which gained fame in the 70s of the last century thanks to the aquarium hobby. Akara, as a rule, do not impose special requirements on the hydrochemical composition of water - all this makes them attractive from the point of view of aquarists. About 30 species of cancer are known.
Origin of the species and description
The assertion wanders from site to site that from the Latin name akara in Russian translation means “stream”. The inconsistency of such a statement is easy to check by referring to the dictionary to make sure - in Latin, the stream is “amnis”. In fact, the acaras got their name thanks to the language of the Guarani Indians, who designate these fish with this word. The semantic meaning of the word is easily accessible. Akara are widespread in the Amazon and for the local inhabitants of the Akara is the same as for the inhabitants of the central part of Russia crucians.
The common name “Akara” covers representatives of several genera of cichlid fish:
- genus Andinoacara;
- genus Aequidens;
- genus Krobia;
- genus Cleithracara;
- genus Bujurquina;
- genus Laetacara.
The currently known types of cancer originate from South America. To date, there is no definite opinion of paleoichthyologists about the common ancestor of cancers. This is due to the insufficient number of fossils found. The oldest prints of acar fish date back to 57 to 45 million years old. This is less than the period of the collapse of Gondwana (135,000,000 years ago), that is, it gives reason to believe that these fish arose already on the territory of modern South America.
The fossils found confirm the point of view that the acaras originally arose in the reservoirs of Peru and in the reservoirs of the Rio Esmeraldes basin. From these places they migrated to other water bodies of the center of South America and today their habitat covers the central part of this continent.
Appearance and features
Acars have a somewhat flattened high body, which is elongated in length. The head of the fish is large, characterized by a characteristic convex forehead. This feature of the structure is more pronounced in males, which have a specific fatty growth on the forehead, which is present to some extent in all cichlids and manifests itself upon reaching maturity.
The eyes of turquoise cancers, in relation to the overall size of the head, are large. The structure of this organ allows fish to see well in the twilight of the underwater part of the reservoir, which, as a rule, is littered with branches and heavily overgrown with aquatic plants. Cancer lips are large. A large number of nerve cell endings are concentrated in this part of the body, which play the role of chemical receptors and enable fish to accurately find both food and partners, to determine the location of the flock.
A characteristic feature of the body structure of turquoise cancers is a rounded caudal fin, as well as pointed anal and dorsal fins. Males have longer fins, often anal and pointed back. Body colors in cancers are diverse and depend on the species. Shades of colors are also diverse - from reddish-burgundy to blue-blue. The color of males is always brighter than that of females.
The sizes of cancers are variable and specific for each species. The smallest — these are maroni akara, the females of which grow up to seven centimeters (males are slightly larger), zebra akara, which grow up to five centimeters. Representatives of bluish-spotted and turquoise acaras grow up to a quarter of a meter.
Where does the turquoise acara live?
The habitat of the acar covers the water bodies of Central and Southern parts of Latin America. Most species live in the mainstream of the Amazon in Colombia, Peru and Brazil.
They are widely represented in such rivers of Brazil, Venezuela and Gaina as:
- Putomayo (Putumayo) ;
- Trombetas;
- Xingu;
- Eskweibo;
- Kapim;
- Branco;
- Negro.
Turquoise acaras are not uncommon in the waters of Trinidad. Akara live mainly in shallow waters with a low flow rate of water rich in tannins. They prefer areas with thickets of aquatic plants, with a bottom topography that provides fish with a large number of shelters. These fish are common for the coastal zone of the reservoir.
Almost all types of cancer prefer to stay near the coast. Preference is given to places densely overgrown with aquatic vegetation, with broad leaves that come to the surface. Such plants provide fish with an opportunity to hide from herons. At the same time, there should be enough space for free swimming, although acars prefer to stay on the territory of the selected site.
What does the Turquoise Acara eat?
Akara are micropredators. That is, the fish swallows its prey whole and tries to swallow it without chewing. Sometimes the imperfection of this type of food intake can be observed in fry of various types of cancer, which are offered live food that is disproportionate in length to the structure of their mouth apparatus. For example, a too long tubifex is not in the stomach, but begins to be carried out with a stream of water passing through the mouth opening and gills - the ends of the tubifex simply hang from the gill slits. The fish, as a result, dies.
The basis of the cancer diet is protein feed. In nature, they feed mainly on larvae of aquatic insects, crustaceans. Some types of acaras, such as turquoise acaras, are well adapted to eating snails. Acaras will not refuse fish, the size of which makes it possible for a predator to swallow the prey whole.
For full development and growth (like all Akara fish grow throughout their lives), the diet should also include a small part of plant foods. Under natural conditions, fish obtain such food by rummaging in deuterium and swallowing particles of semi-decomposed plants. When kept in an aquarium, in addition to protein foods, artificial foods for omnivorous and herbivorous fish are added to the diet.
Social structure and reproduction
Aquarists sometimes call racara the intellectual fish. Fish are distinguished by rather complex behavior, they recognize not only their permanent neighbors, but the owner. They can even be tamed enough to let you pet them.
The social behavior of cancers depends on the species. For example, representatives of the Paraguayan acara species (Latin name Bujurquina vittata), also known among aquarists as acara vittata, are extremely aggressive. Already at the age of a fry, she begins to show intolerance towards same-sex representatives of her species. As they grow older, aggressiveness extends to representatives of any species of fish that make an attempt to swim into the territory that the acara vitata considers its own.
Upon reaching puberty, which occurs by the age of eight months, acara begin to form stable pairs. Acaras are monogamous and mate for life. The parameters by which pairs are formed have not yet been studied, but it is noted that if an adult female is placed next to an adult male, the experiment will end tragically - the male will kill the uninvited guest. Although, on the other hand, if the couple is separated by glass, over time, the male stops trying to expel the female and allows her into his territory.
Having chosen the territory of their habitat, a pair of acaras begins to protect it from the invasion of neighbors. This territory can be quite small, for example, only 100 cm² like Laetacara curviceps, but the couple clearly fixes the boundaries that no one is allowed to cross. An interesting feature of cancer behavior is that aggressiveness is more pronounced in females, who often inspire fights and draw males into them.
The process of reproduction in all types of cancer is similar. Spawning is initiated by an increase in temperature, which is accompanied by an increase in the oxygen content in the water and a decrease in the level of nitrates and nitrites, phosphates, an increase in the softness of the water, and a change in acidity. In nature, this process begins to occur as the volume of water increases as a result of the onset of the frequent rainy season. In aquariums, this change is achieved by increasing the power of aeration, frequent water changes with the addition of distillate.
Readiness for spawning is outwardly manifested by an increase in color intensity and a change in behavior. Akars choose and begin to prepare a place where the eggs will be laid. As a rule, these are flat stones. Aggressiveness of cancers increases - they zealously protect their stone. The surface of the stone is cleaned by fish. In an aquarium, a stone can be replaced with a piece of ceramic, plastic. If they don’t find a suitable object, the acres will start clearing a piece of soil that they think is suitable for spawning.
Recent studies have shown that during spawning, glands located on the lips of cancer cells begin to secrete bactericidal substances. Thus, the fish not only clean the surface, but also disinfect it. At the same time, acars dig something in the ground between a hole and a mink - this is the place where the larvae will be transferred after hatching. Spawning occurs as follows - the female swims over the stone, laying a row of eggs, and the male follows her and fertilizes the eggs.
After spawning, one parent is located above it and ventilates the masonry with the movement of the pectoral fins. The second parent protects the laying place from the penetration of other fish. Some types of cancer after spawning collect eggs in the oral cavity and incubate the eggs in it. As a result of a taxonomic revision carried out by C Kullander in 1986, such cancers were identified as a separate genus Bujurquina. After resorption of the yolk sac in fry, parents begin to feed them - they chew food and release it into a cluster of fry. After the fry acquire the ability to swim freely, the parents do not stop taking care of them. As they grow, the fry leave their parents and develop new habitats.
Natural enemies of turquoise lobsters
Acaras are not of commercial interest for economic activity. The ease of breeding in captivity has led to the loss of interest in these fish from aquarium fish suppliers to the trading networks of America, Europe and Asia, and the low nutritional value does not arouse interest from firms engaged in catching table fish species.
Thus, the circle of enemies of the akara is outlined by predators for whom these fish are natural food. First of all, juvenile caimans can be attributed to such enemies, the diet of which in the first periods of life is based on small fish and large insects. Such an animal as the predatory matamata tortoise is also successfully hunted for acar. Herons of various species, hunting for fish in shallow water, also cause great damage to the populations of acar. The juveniles of such predatory fish as arapaima do not disdain the acaras.
Perhaps the main enemy of the acaras were such skilled hunters as the Brazilian otters. However, a significant reduction in the population of the latter due to human intervention in the nature of the Amazon, brought these predators out of the list of the main enemies of the cancer. At present, no animal has been identified that would prey only predominantly on acar. Therefore, it is impossible to speak of specific enemies of these fish.
Population and species status
Akara easily adapt to life in various conditions. They can be found in slowly flowing rivers, in swampy reservoirs and in streams quickly flowing down from the mountains. Acars are also undemanding to the hydro-chemical composition of water. The range of water hardness, comfortable for life, is wide enough — 3 - 20 dGH. Acidity requirements - pH from 6.0 to 7.5. The temperature range for a comfortable existence is also wide enough - from 22°С to 30°С.
A high degree of adaptation to changing environmental conditions gave the acaras the opportunity not to reduce the size of their population due to changes taking place in the Amazon in results of deforestation. On the contrary, the decrease in the number of natural enemies as a result of human activities, to some extent, even contributed to the increase in the population of these fish in their natural habitats.
Acars are not included in the IUCN Red List of animals and fish (IUCN Red List), therefore, no protective no action is taken against them. The population of these fish in South America is stable and does not show a declining trend.