Intestinal mucosa of the platypus, Ornithorhynchus anatinus
Article first published online: 27 JAN 2005
Copyright © 1975 Wiley-Liss, Inc.
The Anatomical Record
Volume 181, Issue 2, pages 251–265, February 1975
How to Cite
Krause, W. J. (1975), Intestinal mucosa of the platypus, Ornithorhynchus anatinus. Anat. Rec., 181: 251–265. doi: 10.1002/ar.1091810207
- Issue published online: 27 JAN 2005
- Article first published online: 27 JAN 2005
- Manuscript Accepted: 31 JUL 1974
- Manuscript Received: 26 MAR 1974
The intestinal mucosa of the platypus takes the form of numerous transverse surface folds. These folds are made up of a lamina propria covered by pseudostratified epithelium which lies on a thick modified basement membrane. The cells of the intestinal epithelium consist of columnar cells which generally resemble typical intestinal epithelium and cuboidal cells, which are undifferentiated in appearance, show few organelles and possess an electron lucent cytoplasm. Numerous desmosomes are found between the adjacent cell membranes of both cell types. Villi are absent and appear to be represented by the large surface folds.
Intestinal glands are composed of columnar epithelium similar to that found in the intestinal glands of other mammalian species. Groups of these glands drain into common tubular ducts which follow a tortuous course and empty into the intestinal lumen between the surface folds.
The peculiar morphological features of the platypus intestinal mucosa raise questions concerning traditional concepts of intestinal gland formation as well as the origin and migration of intestinal epithelium with regard to this particular species.