108.4 Sunday, Jan. 6 The physiological basis of polychromatic ultraviolet vision in mantis shrimp BOK, MJ*; PORTER, ML; CRONIN, TW; University of Maryland, Baltimore County; University of Maryland, Baltimore County; University of Maryland, Baltimore County firstname.lastname@example.org
Stomatopods, or mantis shrimps, possess the most spectrally diverse retinal photoreceptor array yet described. Their photoreceptors are maximally sensitive to sixteen discrete wavelengths of light between 310 and 700 nm, as well as to linearly and circularly polarized light. The spectral tuning mechanisms at work in these photoreceptors have been well described within the human visible range, above 400 nm, showing that this surprising diversity of photoreceptor types is achieved through unique arrangements of visual pigments and long-pass optical filters in receptor sets of reticular cells 1 to 7 (R1-R7). However, stomatopods also have R8 photoreceptors sensitive to at least five different wavelength ranges of ultraviolet (UV) light, but little is known about their spectral tuning. Here we present molecular and physiological evidence that polychromatic UV vision in the stomatopod Neogonodactylus oerstedii is achieved by the elegant pairwise combinations of one of typically two visual pigments, absorbing at 330 nm and 380 nm respectively, with four novel UV-specific short- and long-pass optical filters. Modeling of photoreceptor spectral sensitivity from the absorbance spectra of these filters and pigments closely matches previous electrophysiological recordings from the R8 receptor cells. Furthermore, various species of stomatopods utilize different complements of these components, producing a diversity of UV receptor suites throughout the order. The sophisticated composition of stomatopod UV photoreceptors suggests an essential role for this capacity in their visual ecology.