Hyphessobrycon ulreyi Boulenger, 1895 Hemigrammus ulreyi, commonly known as Ulrey's tetra, is a Paraguayan tropical aquarium fish from the family Characidae named in honor of the biologist Albert B. Ulrey.

It was originally named Tetragonopterus ulreyi in 1895.

[2] This aquarium fish suitable for a community aquarium can reach 5 cm (2.0 in) in length and does well at temperatures of 21 to 29 °C (70 to 84 °F).

[3] The breeding size is 4 cm (1.6 in).

Dr. Herbert R. Axelrod, editor of Tropical Fish Hobbyist Magazine, and Dr. Leonard P. Schultz, retired curator of fishes at the Smithsonian Institution, wrote that the breeding of this species is a problem, since the species is nearly identical to Hyphessobrycon heterorhabdus and is difficult to spawn.