General and histological structures of different parts of eye in Beaked Sea Snake, Enhydrina schistosa (Daudin 1803)

Kordi, Mansoor; Shabanipou, Nader

doi:10.30473/eab.2019.5987

Document Type : Article

Authors

Mansoor Kordi ¹
Nader Shabanipou ²

¹ Ph.D. in Department of Biology, Faculty of Science, Guilan University, Rasht, Iran

² . Associate Professor in Department of Biology, Faculty of Science, Guilan University, Rasht, Iran

https://doi.org/10.30473/eab.2019.5987

Abstract

Abstract
Study of eye structure in Enhydrina schistosa is an important subject and yet not enough as it is an active hunter that lives in shallow waters and some active predators like sea eagles and sharks are feeding at it. In this study Scanning Electron Microscope (SEM) was used for observing cellular layers in details. Specimens were collected from water surface in Chabahar Bay. The eyes were fixed in Bouin’s fluid and 10% formalin. There is a transparent layer (Spectacle) in front of the cornea (with protective role) with a three-layered structure. The sclera and cornea are quite thick with protective role against water pressure and mechanical stresses. The choroid consists of a loose tissue. The retina is composed of only a few cones and rods are absent that is evidence of the low visual capability in this successful marine reptile. Cone cells density in Ventral (V) and Dorsal (D) quadrants is higher than Temporal (T) and Nasal (N) quadrants and also Cone cells density in Ventral quadrant is higher than Dorsal quadrant. It seems Ventral quadrant (with highest cone cells density) might have a role in detecting aerial predators (sea eagles) and Dorsal quadrant (with lower cone cells density than Ventral quadrant) might have been engaged (not so important) in feeding on demersal fishes.

Keywords

20.1001.1.23222387.1398.8.1.11.7

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Experimental animal Biology

General and histological structures of different parts of eye in Beaked Sea Snake, Enhydrina schistosa (Daudin 1803)

References

References

Volume 8, Issue 1 - Serial Number 29
No.1
August 2019
Pages 123-132

General and histological structures of different parts of eye in Beaked Sea Snake, Enhydrina schistosa (Daudin 1803)

References

References

Volume 8, Issue 1 - Serial Number 29 No.1August 2019Pages 123-132

Volume 8, Issue 1 - Serial Number 29
No.1
August 2019
Pages 123-132