Laughlin S, McGinness S
Cell Tissue Res. 1978 Apr 28;188(3):427-47. doi: 10.1007/BF00219782.
The apposition eyes of the corduliid dragonfly Hemicordulia tau are each divided by pigment colour, facet size and facet arrangement into three regions: dorsal, ventral, and a posterior larval strip. Each ommatidium has two primary pigment cells, twenty-five secondary pigment cells, and eight receptor cells, all surrounded by tracheae which probably prevent light passing between ommatidia, and reduce the weight of the eye. Electron microscopy reveals that the receptor cells are of two types: small vestigial cells making virtually no contribution to the rhabdom, and full-size typical cells. The ventral ommatidia have a distal typical cell (oriented either horizontally or vertically), four medial typical cells, two proximal typical cells and one full-length vestigial cell. The dorsal ommatidia have only four full-length typical cells, and one distal and three vestigial full-length cells. The cross-section of dorsal rhabdoms is small and circular distally, but expands to a large three-pointed star medially and proximally. The tiered receptor arrangement in the ventral ommatidia is typical of other Odonata but the dorsal structure has not been fully described in other species. Specialised dorsal eye regions are typical of insects that detect others against the sky.
束翅蜻蜓Hemicordulia tau的并列复眼各自通过色素颜色、小眼面大小和小眼面排列被划分为三个区域：背侧、腹侧和一条后部幼虫带。每个小眼都有两个初级色素细胞、二十五个次级色素细胞和八个感受器细胞，所有这些细胞都被气管包围，气管可能会阻止光线在小眼之间穿过，并减轻眼睛的重量。电子显微镜显示感受器细胞有两种类型：对视杆几乎没有贡献的小残迹细胞和全尺寸的典型细胞。腹侧小眼有一个远端典型细胞（水平或垂直定向）、四个中间典型细胞、两个近端典型细胞和一个全长残迹细胞。背侧小眼只有四个全长典型细胞，以及一个远端和三个全长残迹细胞。背侧视杆的横截面在远端较小且呈圆形，但在中间和近端扩展为一个大的三角形星状。腹侧小眼的分层感受器排列是其他蜻蜓目的典型特征，但背侧结构在其他物种中尚未得到充分描述。专门的背侧眼区是在天空中探测其他物体的昆虫的典型特征。
