Structure and arrangement of photoreceptors in the retina of big eye kilka, Clupeonella grimmi (Kessler 1877)
The big eye kilka, Clupeonella grimmi, is a marine fish living in depth of 20 to 200 meter of the Caspian Sea. Its eye and retina were processed for histological and SEM studies. Paraffin embedded retina was cut radially and tangentially in 5 µm thickness and stained with hematoxylin and eosin met...
| Main Authors: | , , |
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| Format: | Article |
| Language: | English |
| Published: |
University of Guilan
2014-10-01
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| Series: | Caspian Journal of Environmental Sciences |
| Subjects: | |
| Online Access: | https://cjes.guilan.ac.ir/article_1133.html |
| Summary: | The big eye kilka, Clupeonella grimmi, is a marine fish living in depth of 20 to 200 meter of the Caspian
Sea. Its eye and retina were processed for histological and SEM studies. Paraffin embedded retina was
cut radially and tangentially in 5 µm thickness and stained with hematoxylin and eosin method. The
unstained sections were manipulated for SEM image observations. Tangential retinal sections showed
irregular arrangement of cones. Five morphologically different types of photoreceptors were
distinguished as rods, short single cones, long single cones, twin cones and double cones. The cones were
counted in each quadrant of the retina and cone density was determined. The cones showed increment in
diameter but reduction in number at anti-clockwise direction without any specific arrangement. Presence
of four types of cone cells and their pattern of distribution revealed assistance in near surface color vision
and more light capture in dim light of deeper waters as an adaptation to planktivorous feeding habit and
deep water living habitat. |
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| ISSN: | 1735-3033 1735-3866 |