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Published on: October 6, 2019
Corneal microprojections in coleoid cephalopods.
Christopher Talbot1, Thomas M Jordan, Nicholas W Roberts
1Sensory Neurobiology Group, Queensland Brain Institute and School of Biomedical Sciences, The University of Queensland, St Lucia, Brisbane, QLD, 4072, Australia.
Summary
Cephalopods possess unique nipple-like microprojections on their corneas, unlike vertebrates. These structures may enhance cellular exchange or mucous layer stability, rather than providing an anti-reflective surface.
Area of Science:
- Ophthalmology
- Comparative Anatomy
- Microscopy
Background:
- The cornea, the eye's primary optical surface, features microprojections in vertebrates and some invertebrates.
- Cephalopods, with camera-type eyes, were previously unexamined for corneal microprojections.
Purpose of the Study:
- To investigate the presence and morphology of corneal microprojections in cephalopods.
- To determine the potential function of these structures in cephalopod corneas.
Main Methods:
- Scanning electron microscopy was employed to examine the corneal surfaces of various cephalopod species.
- Morphological analysis of discovered microprojections was conducted.
Main Results:
- All examined cephalopod species exhibited nipple-like microprojections on their corneas.
- These nipples varied in arrangement (hexagonal to irregular) and size (75-103 nm).
- Cephalopod nipples do not appear to serve an anti-reflective function due to optical properties.
Conclusions:
- Cephalopods possess distinct corneal nipple microprojections.
- Potential functions include increased cellular exchange or stabilization of the corneal mucous layer.
- Further research is needed to elucidate the precise role of these structures.
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