Eye Ultrastructure of three Ecologically Diverse Elaterid Beetle species (Coleoptera: Elateridae)
The structural organization of the compound eyes of three elaterid beetles, i. e, Agrypnus binodulus Motschulsky 1861, Melanotus legatus Candèze 1860 and Melanotus cete Candèze 1860 have been examined by light and electron microscopy techniques. The result of this structural investigation gives the basis for a comparison between eye morphology with ecology and activity of the beetles. Superposition type of eye with exocone type of cone along with tiered arrangement of rhabdom is observed for all the examined species. Variations were detected in the dimension of the ommatidium, cone length, clear zone size, rhabdom length and diameter for different species. Furthermore the microvilli size of the distal rhabdom is found to be larger than the proximal rhabdom. In summary, the eye ultrastructure of the analyzed species is adapted differently to cope with various environmental light intensities.
Agrypnus binodulus Motschulsky 1861 • Melanotus legatus Candèze 1860 • Melanotus cete Candèze 1860 • clear zone • ecological variation • eye ultrastructure • rhabdom occupation ratio • superposition eye • tiered rhabdom