Kleinlogel Sonja, Marshall N Justin
Vision Touch and Hearing Research Centre, School of Biomedical Sciences, University of Queensland, Brisbane QLD 4072, Australia.
J Exp Biol. 2006 Nov;209(Pt 21):4262-72. doi: 10.1242/jeb.02499.
Gonodactyloid stomatopod crustaceans possess polarization vision, which enables them to discriminate light of different e-vector angle. Their unusual apposition compound eyes are divided by an equatorial band of six rows of enlarged, structurally modified ommatidia, the mid-band (MB). The rhabdoms of the two most ventral MB rows 5 and 6 are structurally designed for polarization vision. Here we show, with electrophysiological recordings, that the photoreceptors R1-R7 within these two MB rows in Gonodactylus chiragra are highly sensitive to linear polarized light of two orthogonal directions (PS=6.1). They possess a narrow spectral sensitivity peaking at 565 nm. Unexpectedly, photoreceptors within the distal rhabdomal tier of MB row 2 also possess highly sensitive linear polarization receptors, which are in their spectral and polarization characteristics similar to the receptors of MB rows 5 and 6. Photoreceptors R1-R7 within the remainder of the MB exhibit low polarization sensitivity (PS=2.3). Outside the MB, in the two hemispheres, R1-R7 possess medium linear polarization sensitivity (PS=3.8) and a broad spectral sensitivity peaking at around 500 nm, typical for most crustaceans. Throughout the retina the most distally situated UV-sensitive R8 cells are not sensitive to linear polarized light.
蝉形口足类甲壳动物具有偏振视觉，这使它们能够辨别不同电场矢量角的光。它们不同寻常的并列复眼被一条由六排扩大的、结构经过修饰的小眼组成的赤道带隔开，即中带（MB）。最腹侧的MB第5排和第6排的视杆在结构上是为偏振视觉设计的。在这里，我们通过电生理记录表明，蝉虾（Gonodactylus chiragra）这两排MB中的光感受器R1 - R7对两个正交方向的线偏振光高度敏感（偏振度PS = 6.1）。它们具有在565 nm处达到峰值的窄光谱敏感性。出乎意料的是，MB第2排远端视杆层内的光感受器也具有高度敏感的线偏振感受器，其光谱和偏振特性与第5排和第6排的感受器相似。MB其余部分内的光感受器R1 - R7表现出低偏振敏感性（PS = 2.3）。在MB之外，在两个半球中，R1 - R7具有中等线偏振敏感性（PS = 3.8）和在500 nm左右达到峰值的宽光谱敏感性，这是大多数甲壳类动物的典型特征。在整个视网膜中，最远端的对紫外线敏感的R8细胞对线偏振光不敏感。
