Dictionary of Ichthyology  

zebrafish = Danio rerio (formerly Brachydanio rerio), a member of the Cyprinidae used to study vertebrate biology, physiology, genetics, developmental biology, neurology and human disease. It has a short generation time, is highly fecund, fry are transparent, and many mutants with features resembling human diseases have been identified.

Fluorescent zebrafish (GloFish) from Wikimedia Commons: http://commons.wikimedia.org/wiki/File:GloFish.jpg

Canadian Museum of Nature
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