1. A class of visual pigments found in the retinas of certain fish and other aquatic vertebrates, similar to rhodopsin but with a different light-absorbing wavelength.
Usage: technical; biology; plural form of porphyropsin

Examples

• Porphyropsins are photosensitive proteins that enable vision in freshwater fish.
• The presence of porphyropsins in deep-sea creatures helps them detect bioluminescence.
• Unlike rhodopsin, porphyropsins absorb light at different wavelengths suited to aquatic environments.
• Scientists study porphyropsins to understand how different species adapt to their visual habitats.