Buenos Aires tetra

fish

Also known as: Hemigrammus caudovittatus

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Last updated

June 22, 2026

Quick Summary

The Buenos Aires tetra is a species of freshwater fish belonging to the characin family, Characidae. These fish are native to South America and are known for being small, lively, hardy, and unaggressive, making them popular in home aquariums. The Buenos Aires tetra can grow up to 9 cm (3.5 inches) long and is characterized by its reddish fins and a dark stripe along each side that widens into a diamond-shaped spot near the tail. The name "tetra" originates from a genus name, Tetragonopterus, and while no longer scientifically significant, it remains a common popular name for these fish.1

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tetra
The Buenos Aires tetra (Hemigrammus caudovittatus) grows to 9 cm; it has reddish fins and a dark, lengthwise stripe on each side that widens to a diamond-shaped spot on each side of the tail root.
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The Buenos Aires tetra (Hemigrammus caudovittatus) grows to 9 cm; it has reddish fins and a dark, lengthwise stripe on each side that widens to a diamond-shaped spot on each side of the tail root.
Read More