#cypriniformes

The Bigmouth Buffalo (Ictiobus cyprinellus) can reach an age of up to 127 years, making it the oldest known freshwater teleost fish.

The Indonesian Superdwarf Fish (Paedocypris progenetica) is one of smallest known species of fish in the world. The smallest mature female measured 7.9 mm (0.31 in) and the largest known individual was 10.3 mm (0.41 in).

The critically endangered Giant Barb (Catlocarpio siamensis) (image 1) is the largest species of Cyprinid, with an unconfirmed maximum length of 3 m (9.8 ft) and weight up to 300 kg (660 lb).

The Pacific Redfin (Pseudaspius brandtii) is the only Cypriniform known to inhabit salt water, and is found from the Siberian Pacific Coast through coastal Japan.

At least three loach families contain blind, troglomorphic species adapted to life in caves.

The Tench (Tinca tinca) has very small scales, which are deeply embedded in a thick skin, making it as slippery as an eel. Folklore has it that this slime cured any sick fish that rubbed against it, and from this belief arose the another common name: Doctor Fish.

The Common Carp (Cyprinus carpio) is declining and even rated vulnerable in some of its native habitat, though introduced populations have become invasive in other environments worldwide, and it is considered one of the world’s most destructive invasive species.

The bitterlings of subfamily Acheilognathinae are notable for depositing their eggs in bivalve molluscs, where the young develop until able to fend for themselves.

The herbivorous Grass Carp (Ctenopharyngodon idella) is both cultivated for food and for aquatic weed control, and has been introduced into many areas to control undesirable aquatic vegetation. In China it is known as one of the "Four Great Domestic Fish".

The Thicktail Chub (Gila crassicauda), a type of minnow, was once the most common freshwater fish found in California. The chub was a favored food of the indigenous peoples of Clear Lake and the Central Valley, before it became heavily exploited by colonist commercial fishermen supplying the San Francisco market. Most of its habitat was also destroyed by the drainage of sloughs and marshes, dam-building, and water diversion for irrigation. The last known Thicktail Chub was caught on April 16, 1957. Just 70 years after being considered the most common freshwater fish in California, not a single living individual existed.

The critically endangered Red-tailed Black Shark (Epalzeorhynchos bicolo) (image 4) is popular in the home aquarium trade, but may in fact be extinct in its native habitat of Thailand.

Almost all domesticated fish belong to the Cypriniformes, and include the Koi (Cyprinus rubrofuscus var. koi or nishikigoi) (see gif above), Goldfish (Carassius auratus), and Zebrafish (Danio rerio), which have all been bred to display a variety of colors, patterns, fin types, and even body shapes.

The Zebrafish is one of the most important vertebrate model organisms in biological and biochemical studies, being used in many kinds of experiments. During early development, the zebrafish has a nearly transparent body, so it is ideal for studying developmental biology. It is also used for the elucidation of biochemical signaling pathways.

I have 6 Black Ruby Barbs (Pethia nigrofasciata) whomst I love with all my heart, and they turn deep purple and get the zoomies when they’re excited (usually when I feed them in the morning, when I come home from work, and after I clean the tank).