Meyer-Rochow V B, Walsh S
Cell Tissue Res. 1978 Dec 14;195(1):59-79. doi: 10.1007/BF00233677.
The compound eyes of the mesopelagic eupausiid Thysanopoda tricuspidata were investigated by light-, scanning-, and transmission electron microscopy. The eyes are spherical and have a diameter that corresponds to 1/6 of the carapace length. The hexagonal facets have strongly curved outer surfaces. Although there are four crystalline cone cells, only two participate in the formation of the cone, which is 90-120 micrometer long and appears to have a radial gradient of refractive index. The clear zone, separating dioptric structures and retinula, is only 90-120 micrometer wide. In it lie the very large oval nuclei of the seven retinula cells. Directly in front of the 70 micrometer long and 15 micrometer thick rhabdom a lens-like structure of 12 micrometer diameter is developed. This structure, known in only a very few arthropods, seems to be present in all species of Euphausiacea studied to date. It is believed that the rhabdom lens improves near-field vision and absolute light sensitivity. Rod-shaped pigment grains and mitochondria of the tubular type are found in the plasma of retinula cells. The position of the proximal screening pigment as well as the microvillar organization in the rhabdom are indicative of light-adapted material. The orthogonal alignment of rhabdovilli suggests polarization sensitivity. Behind each rabdom there is a cup-shaped homogenous structure of unknown, but possibly optical function. Finally, the structure and the function of the euphysiid eye are reviewed and the functional implications of individual components are discussed.
利用光学显微镜、扫描电子显微镜和透射电子显微镜对中层磷虾三尖瓣磷虾的复眼进行了研究。眼睛呈球形，直径相当于头胸甲长度的1/6。六边形小眼面的外表面有强烈的弯曲。虽然有四个晶锥细胞，但只有两个参与晶锥的形成，晶锥长90 - 120微米，似乎具有径向折射率梯度。分隔屈光结构和视网膜的透明区仅90 - 120微米宽。其中有七个视网膜细胞的非常大的椭圆形细胞核。在70微米长、15微米厚的视杆前方直接发育出一个直径为12微米的透镜状结构。这种结构仅在极少数节肢动物中已知，似乎在迄今为止研究的所有磷虾种类中都存在。据信，视杆透镜可改善近场视觉和绝对光敏感度。在视网膜细胞的细胞质中发现了杆状色素颗粒和管状线粒体。近端屏蔽色素的位置以及视杆中的微绒毛组织表明是适应光的物质。视杆微绒毛的正交排列表明具有偏振敏感性。在每个视杆后面有一个杯状的均匀结构，其功能未知，但可能具有光学功能。最后，对磷虾眼的结构和功能进行了综述，并讨论了各个组成部分的功能意义。
