Dictionary of Ichthyology  

Matsya = fish in Sanskrit (मत्स्य) and the first avatar of Vishnu in Hindu mythyology, usually represented as a man with his lower half in the shape of a fish. See also Matsyendra and Mathsyendranath.

From a devotional text, Wikimedia Commons: http://en.wikipedia.org/wiki/File:Matsya_
painting.jpg

Canadian Museum of Nature
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