The Ultrastructure of the Spectacle, Cornea and Conjunctiva of the Short-Nosed Sea Snake Aipysurus apraefrontalis (Elapidae, Squamata) With Particular Reference to the Sub-Spectacular Space and Its Contents.

Λεπτομέρειες βιβλιογραφικής εγγραφής
Τίτλος:	The Ultrastructure of the Spectacle, Cornea and Conjunctiva of the Short-Nosed Sea Snake Aipysurus apraefrontalis (Elapidae, Squamata) With Particular Reference to the Sub-Spectacular Space and Its Contents.
Συγγραφείς:	Collin HB; Department of Optometry and Vision Science, University of New South Wales, Kensington, New South Wales, Australia., Liu B; Bioimaging Platform, La Trobe University, Bundoora, Victoria, Australia., Wilson S; Bioimaging Platform, La Trobe University, Bundoora, Victoria, Australia., Crowe-Riddell JM; School of Biological Sciences, Adelaide University, Adelaide, South Australia, Australia., Collin SP; School of Agriculture, Biomedicine and Environment, La Trobe University, Bundoora, Victoria, Australia.; Max Planck Queensland Centre (MPQC) for the Materials Science of Extracellular Matrices, Queensland University of Technology, Brisbane, Queensland, Australia.
Πηγή:	Journal of morphology [J Morphol] 2026 Sep; Vol. 287 (9), pp. e70177.
Τύπος έκδοσης:	Journal Article
Γλώσσα:	English
Στοιχεία περιοδικού:	Publisher: Wiley Country of Publication: United States NLM ID: 0406125 Publication Model: Print Cited Medium: Internet ISSN: 1097-4687 (Electronic) Linking ISSN: 00222887 NLM ISO Abbreviation: J Morphol Subsets: MEDLINE
Imprint Name(s):	Publication: <2005- > : Hoboken, N.J. : Wiley Original Publication: 1931- : Philadelphia, Pa. : Wistar Institute of Anatomy and Biology
Ιατρικοί όροι (MeSH):	Conjunctiva/ultrastructure , Cornea/ultrastructure , Elapidae*/anatomy & histology, Animals ; Microscopy, Electron, Transmission
Περίληψη:	The eyes of snakes possess an outer protective spectacle, continuous with the dermis, and an inner cornea, continuous with the scleral eyecup, that encloses a fluid-filled space. While the spectacle and cornea provide transparency and contribute to the refractive power of the eye, little is known of their ultrastructure and role in maintaining the contents of the sub-spectacular space. Using micro computed tomography, light microscopy and transmission electron microscopy, this study reveals that the conjunctival portions of the corneal epithelial and spectacular endothelial lining of the short-nosed sea snake Aipysurus apraefrontalis possess high densities of microvilli to increase the surface area and aid in intra- and extracellular movement of nutrients and waste products, and at least two types of vesicles that contain what appear to be mucin fibrils and actin filaments, respectively, that may play a role in secretion of their contents into the sub-spectacular space. The discovery of several ducts in the conjunctiva suggests that the Harderian gland may also deliver (non-lipid-bearing) fluid and granules to this space via several routes. The likely functions of the conjunctival secretory tissue are discussed in the context of maintaining the fluid within the sub-spectacular space and the need to assist in the control of smooth eye movements beneath the immobile spectacle. (© 2026 The Author(s). Journal of Morphology published by Wiley Periodicals LLC.)
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Grant Information:	DP230101438 Australian Research Council; DE240100501 Australian Research Council; La Trobe University; Max Planck Queensland Centre (MPQC)
Contributed Indexing:	Keywords: adnexa; conjunctival sac; glandular tissue; mucin; secretion; sub‐spectacular space; vesicles
Entry Date(s):	Date Created: 20260919 Date Completed: 20260919 Latest Revision: 20260923
Update Code:	20260923
PubMed Central ID:	PMC13589157
DOI:	10.1002/jmor.70177
PMID:	42760767
Βάση Δεδομένων:	MEDLINE

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