Dictionary of Ichthyology  

asymmetrical = lacking symmetry, e.g. Bothidae and Pleuronectidae lack bilateral symmetry, one eye rotating to the other side of the head.

Pleuronectes (= Platichthys) flesus from Lydekker et al. "Reptiles, Amphibia, Fishes and Lower Chordata", 1912. Photograph by Brian W. Coad.

Canadian Museum of Nature
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