Phototaxis of adult brine shrimp, Artemia salina

Using phototaxis as a behavioral measure of light perception, spectral and intensity sensitivity were determined for adult brine shrimp, Artemia salina. Spectral sensitivity was characterized by a well-defined maximum at 520 nm light, with perhaps a smaller maximum at 400 nm light. Dark-adapted animals showed a strong negative phototaxis at high intensities between 5.0 × 1012 quanta∙m−2∙s−1 and 3.6 × 1016 quanta∙m−2∙s−1 at 520 nm light. Positive phototaxis was greatest at the low intensity of 2.8 × 1012 quanta∙m−2∙s−1. Threshold sensitivity for both positive and negative phototaxis was approximately 2 × 1012 quanta∙m−2∙s−1.