There are eighteen subfamilies of non-visual opsins, when subfamily is defined as a clade with tetrapod and ray-finned fish orthologs. An amphibian sequence occurred in every subfamily, whereas Mammalia was represented in only seven. Fish species representing Holostei, Osteoglossomorpha, Otomorpha, Protacanthopterygii, Cyprinodontoidei, and Pleuronectiformes all had a large number of non-visual opsins (from 22 to 32 genes) as a result of ancient gene duplication events including, but not limited to, the teleost genome duplication (TGD). The non-visual opsin repertoire appears to have stabilized shortly after the TGD event and consequently these distantly related fishes had repertoires of similar size and composition. This differs from the pattern observed for visual opsins, where large fish repertoires were generated by relatively recent lineage-specific duplications. Most non-visual opsins have been named without the benefit of a phylogenetic perspective. We propose major revisions.