Hemigrammus hyanuary
species of fish
Hemigrammus hyanuary, the January tetra or Costello tetra, is a species of freshwater ray-finned fish belonging to the family Acestrorhamphidae. This fish is found in the Amazon Basin in South America. This species is uncommonly found in the aquarium trade.
Taxonomy
Hemigrammus hyanuary was first formally described in 1918 by the American entomologist and ichthyologist Marion Durbin Ellis, with its type locality given as Lake Hyanuary in Brazil. This species belongs to the genus Hemigrammus, which is classified in the subfamily Pristellinae of the American characin family Acestrorhamphidae. This family is classified within the suborder Characoidei of the order Characiformes.
Distribution
Costello tetras are found in the Amazon Basin.
In the aquarium
Costello tetras have been kept in the aquarium hobby. Some foods aquarists feed them include flakes, pellets, and live foods. Wild caught specimens sport a characteristic golden sheen to their scales; the presence of a parasite found within their native range that causes this unusual pigmentation.
This brief starts where responsible research should: with the source description of “Hemigrammus hyanuary” as species of fish. Everything that follows is an evidence route, not borrowed authority.
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The subject matters to the science & nature register because the source frames it as species of fish. Its deeper value depends on whether names, dates, institutions and citations support that framing.
Datasets, specimens, observations and peer-reviewed methods provide the appropriate test for the technical claims summarized here. The source revision retrieved here is dated Sep 1, 2026. The linked authority identifier is Q178523. None of the 0 selected statements returned an explicit reference. The first chronological checks are 1918.
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This entry incorporates text from “Hemigrammus hyanuary” on English Wikipedia. Contributors are listed in the page history. Text is available under the Creative Commons Attribution-ShareAlike 4.0 License. Selected authority identifiers and statements are retrieved from Wikidata under CC0; their references and qualifiers remain part of the verification path.