Analysis of visual pigment absorbance and luminescence emission spectra in marine ostracodes (Crustacea: Ostracoda)

Abstract

1. 1. The luminescence emission spectra and the visual pigment absorbance spectra in digitonin extracts were examined and compared for marine luminescent ostracodes. 2. 2. The rhodopsin absorbance spectrum of one non-luminescent species was determined for comparison. 3. 3. For all species examined ( Vargula tsujii, V. graminicola and Skogsbergia lerneri), the difference spectra for visual pigment absorbance peaked at 460 nm. 4. 4. The luminescence emission spectra were measured by means of a computer controlled optical multi-channel analyser (OMA). 5. 5. For the two luminescent species examined ( V. graminicola and V. shulmanae), the λ max of the emitted light was 473 nm with full width at half maxima (FWHM) of about 80 nm. 6. 6. The luminescence emission spectra were also determined for male/female, adult/juvenile and dried/live pairs of V. graminicola. 7. 7. All had a λ max of 473 nm and in all cases the curves were unimodal with the FWHM of 80 nm. 8. 8. V. graminicola and V. shulmanae are found in Panama in the Caribbean and the males emit their luminescence in complex display patterns (signals) for purposes of attracting receptive females. 9. 9. Since the emission spectra for these two signalling species were similar, it would appear that species recognition is not based on wavelength but rather some other aspect of the luminescent display.