The plica semilunaris is the thin upper part of the fold of
mucous membrane
A mucous membrane or mucosa is a membrane that lines various cavities in the body of an organism and covers the surface of internal organs. It consists of one or more layers of epithelial cells overlying a layer of loose connective tissue. It is ...
in the
supratonsillar fossa that reaches across between the two arches. A separate fold is called the
plica triangularis which runs inferoposteriorly from the posterior surface of the palatoglossal arch to cover the inferior portion of the tonsil.
References
Palate
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