The zebrafish (Danio rerio) is a freshwater fish belonging to the minnow family (Cyprinidae) of the order Cypriniformes. Native to South Asia, it is a popular aquarium fish, frequently sold under the trade name zebra danio (and thus often called a "tropical fish" although both tropical and subtropical).

The zebrafish is an important and widely used vertebrate model organism in scientific research, for example in drug development, in particular pre-clinical development. It is also notable for its regenerative abilities, and has been modified by researchers to produce many transgenic strains.

 

Note:   The above text is excerpted from the Wikipedia article Zebrafish, which has been released under the GNU Free Documentation License.