Flagtail Characin

Semaprochilodus theraponura

A silvery Amazon fish with boldly striped black-and-orange tail fins that migrates upriver to spawn.

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About the Flagtail Characin

Flagtail characins grow up to about 14 inches long. They have flat, silver bodies, a reddish-orange belly fin and tail fins with bold black and orange stripes. They live in rivers of the central and western Amazon, near the bottom. They eat fine, mushy material from the river bottom that is full of tiny living things.^[1]

Quick facts

Scientific name: Semaprochilodus theraponura^[1]
Size: Up to about 14 inches long.^[1]
Diet: Detritus and fine bottom material rich in microorganisms.^[1]
Habitat: Freshwater rivers, near the bottom.^[1]
Where it lives: Central and western Amazon tributaries.^[1]
Babies: Migrates upriver to spawn and lay eggs.^[1]
Conservation status: Not evaluated by the IUCN.^[1]

Fun facts

Their striped tail fins look like flags.^[1]
They migrate upriver with the yearly floods.^[1]
They're also called kissing prochilodus.^[1]

Vocabulary

fish: A cold-blooded animal that lives in water, breathes with gills and usually has fins and scales.
detritus: Bits of dead plants and animals.
spawn: To release or lay eggs in water.
migrate: To travel from one region to another with the seasons.
oviparous: Laying eggs that hatch outside the mother's body.

See it in person

Smithsonian's National ZooWashington, D.C. · AmazoniaSee this animal on the zoo's website ↗

These zoos had this animal when we gathered our information, but animals sometimes move. Check the zoo's website or contact the zoo before you visit.

Sources

[1] Smithsonian's National Zoo & Conservation Biology Institute. “Flagtail characin.” https://nationalzoo.si.edu/animals/flagtail-characin (accessed 2026-10-08)

Facts last checked 2026-10-08.

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