Acestrorhamphidae

cardinal tetra

Paracheirodon axelrodi

Iridescent blue line over vivid red body

• Tropical
• Upper river
• Southern Hemisphere
• Regional distribution
• Freshwater fish
• South America
• Small
• Tropical fish

The cardinal tetra (Paracheirodon axelrodi) is a species of freshwater fish of the family Acestrorhamphidae, the American characins, of order Characiformes. It is native to the upper Orinoco and Negro Rivers in South America. Growing to about 3 cm (1.2 in) in total length, the cardinal tetra has the striking iridescent blue line characteristic of the genus Paracheirodon laterally bisecting the fish, with the body below this line being vivid red in color, hence the name "cardinal tetra".