The Tissue (Triphosa dubitata, Linnaeus 1758) is a moth, which spends most of its adult lifetime in caves. In its winter (hybernating) stage we expected a reduction of structural and functional properties of the retina. We used histological (light microscopy) and electrophysiological methods (ERG, intracellular sharp electrode recordings) to determine the properties of tissue's compound eye and ommatidia, temperature dependence of photoreceptor response, spectral, polarisation and absolute sensitivity, corner frequency, information capacity and passive electric properties of the photoreceptor membrane. The results have been supplemented with electrophysiological measurements on other moth species. In the Tissue, we didn't find any observable reduction of rhabdom size and functional properties of the photoreceptors. The corner frequency and information capacity of tissue photoreceptors are comparable to other nocturnal species. In related species the speed of vision was increased with the temperature, but only up to ~30 °C. The absorption peak of the main photoreceptors in the tissue is at 505 nm, compared to ~520 nm in other moths. Moth photoreceptors in the dorsal rim area have high polarisation sensitivity and absorption peak in the green, which is an adaptation to the detection of celestial pattern of polarisation by night. Photoreceptors with potentially high polarisation sensitivity are present also in distal parts of the main retina. The eye of the tissue seems to have less ommatidia than facets. The image on the retina is thus undersampled, which is probably an adaptation to poorly focussed image in the superposition eye and extensive spatial summation at the level of the visual interneurons.
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