Nematobrycon palmeri

Nematobrycon palmeri, commonly known as the emperor tetra, is a species of freshwater ray-finned fish belonging to the family Acestrorhamphidae, the American tetras. This species is found in the Atrato and San Juan river basins in western Colombia. It was first imported in the aquarium trade to the United States in 1960 and has since become well established.

It is named in honor of Mervyn George Palmer (1882–1954), an English traveler who collected in Central and South America for the British Museum, and who collected the type specimen.