The Congo tetra (''Phenacogrammus interruptus'') is a species of fish in the African tetra family, found in the central

Congo River Basin The Congo River, formerly also known as the Zaire River, is the second-longest river in Africa, shorter only than the Nile, as well as the third-largest river in the world list of rivers by discharge, by discharge volume, following the Amazon Ri ...

Africa Africa is the world's second-largest and second-most populous continent after Asia. At about 30.3 million km2 (11.7 million square miles) including adjacent islands, it covers 20% of Earth's land area and 6% of its total surfac ...

. It is commonly kept in aquaria.

Description

The Congo tetra has a typical full-bodied

tetra Tetra is the common name of many small freshwater characiform fishes. Tetras come from Africa, Central America, and South America, belonging to the biological families Characidae, Alestidae (the "African tetras"), Lepidarchidae, Lebiasi ...

shape with rather large scales. When mature, the

iridescent Iridescence (also known as goniochromism) is the phenomenon of certain surfaces that appear gradually to change colour as the angle of view or the angle of illumination changes. Iridescence is caused by wave interference of light in microstruc ...

colors of the Congo tetra run through the fish from front to back, starting with blue on top changing to red through the middle, to yellow-gold, and back to blue just above the belly. It is not its

fluorescent Fluorescence is one of two kinds of photoluminescence, the emission of light by a substance that has absorbed light or other electromagnetic radiation. When exposed to ultraviolet radiation, many substances will glow (fluoresce) with color ...

colors that make this tetra so distinct, but rather its tail fin, which develops into a grayish-violet feathery appendage with white edges. The males get up to 3.0 inches (8.5 cm). Females up to 2.75 inches (6 cm). The male is larger with more color, also the tail fin and dorsal fin are more extended. They also have different colors and extensions in the caudal fin.

Aquarium trade and keeping

Congo tetra are a popular

aquarium An aquarium (: aquariums or aquaria) is a vivarium of any size having at least one transparent side in which aquatic plants or animals are kept and displayed. fishkeeping, Fishkeepers use aquaria to keep fish, invertebrates, amphibians, aquati ...

species.

Breeding

Congo tetras are egg-scattering fish that exhibit no parental care. They are known to

spawn Spawn or spawning may refer to: * Spawning, the eggs and sperm of aquatic animals Arts, entertainment and media * Spawn (character), a fictional character in the comic series of the same name and in the associated franchise ** ''Spawn: Armageddon' ...

in groups or in pairs, with breeding typically occurring in soft, slightly acidic to neutral water conditions (pH 6.0–7.5) with a temperature range of 75–80°F (24–27°C). A dimly lit environment and the presence of fine-leaved plants or a spawning mop are beneficial, as the species tends to scatter eggs among vegetation. During

courtship Courtship is the period wherein some couples get to know each other prior to a possible marriage or committed romantic, ''de facto'' relationship. Courtship traditionally may begin after a betrothal and may conclude with the celebration of marri ...

, males display intensified coloration and extended fin rays while performing a display to attract females. Once spawning occurs, the female releases several hundred adhesive eggs, which settle among the plants or substrate. The eggs typically hatch within 6 to 7 days, depending on water temperature, and the fry become free-swimming shortly thereafter. Due to their tendency to consume their own eggs, it is common practice in controlled breeding conditions to separate the adult fish after spawning. The fry require

microscopic The microscopic scale () is the scale of objects and events smaller than those that can easily be seen by the naked eye, requiring a lens or microscope to see them clearly. In physics, the microscopic scale is sometimes regarded as the scale betwe ...

food such as

infusoria Infusoria is a word used to describe various freshwater microorganisms, including ciliates, copepods, Euglena, euglenoids, planktonic crustaceans, protozoa, unicellular algae and small invertebrates. Some authors (e.g., Otto Bütschli, Bütschli) ...

or liquid fry food initially, before transitioning to baby brine shrimp and finely crushed flake food as they grow. Growth is relatively fast under optimal conditions, with juveniles developing their characteristic iridescent colors and elongated fins as they mature. Congo tetras reach

sexual maturity Sexual maturity is the capability of an organism to reproduce. In humans, it is related to both puberty and adulthood. ''Puberty'' is the biological process of sexual maturation, while ''adulthood'', the condition of being socially recognized ...

at approximately 9 to 12 months of age. Successful breeding in home aquariums can be challenging, often requiring careful monitoring of water parameters and the use of a separate breeding tank to optimize survival rates.

Conservation status

The

IUCN The International Union for Conservation of Nature (IUCN) is an international organization working in the field of nature conservation and sustainable use of natural resources. Founded in 1948, IUCN has become the global authority on the status ...

lists the Congo tetra as a species of

Least Concern A least-concern species is a species that has been evaluated and categorized by the International Union for Conservation of Nature (IUCN) as not being a focus of wildlife conservation because the specific species is still plentiful in the wil ...

Sources

*Ultrastructural Examination of Spermiogenesis and Spermatozoon Ultrastructure in Congo tetra Phenacogrammus interruptus Boulenger, 1899 (Ostariophysi: Characiformes: Alestidae) :Author: Pecio, Anna :Folia Biologica, Volume 57, Numbers 1–2, December 2008, pp. 13–21(9) :Publisher: Institute of Systematics and Evolution of Animals, Polish Academy of Sciences *

IUCN Red list The International Union for Conservation of Nature (IUCN) Red List of Threatened Species, also known as the IUCN Red List or Red Data Book, founded in 1964, is an inventory of the global conservation status and extinction risk of biological ...

References

External links

*
Fishbase

Congo Tetra Fact Sheet
{{Taxonbar, from=Q530817 Phenacogrammus Freshwater fish of Africa Fish described in 1899 Taxa named by George Albert Boulenger