HISTOCHEMISTRY OF THE EPITHELIAL, MUCOUS AND CLUB CELLS OF OPERCULR EPIDERMIS OF A PEPPERED LOACH, LEPIDOCEPHALICHTHYS GUNTEA.

The present investigation aims to study the structural organization of epidermis, covering the outer surface of the operculum (OE) of a peppered loach, Lepidocephalichthys guntea. The patterns of micro ridges on the epithelial cells, composition of glycoprotein, elaborated by mucous cells and distribution of taste buds on the surfaces of the OE of the Lepidocephalichthys guntea, may be considered as modifications relating to possible differences in the functional requirements at the two locations. In the OE of the Lepidocephalichthys guntea, compactly arranged micro ridges provide rigidity to the free surfaces of the epithelial cells. This is an adaptation to withstand mechanical stress and protect the surface of the fish, which has the characteristic habit of bottom dwelling and burrowing in mud during drought. The high rate of the elaboration of the glycoprotein in the OE by mucous cells in the Lepidocephalichthys guntea is related to the increased viscosity of the mucous and the lubrication of the surface of the fish. It plays a vital role in providing protection to the body against mechanical damages and provides high resistance against pathogens. The presence of prominent taste buds in the OE might be considered to increase the probability of accurately detecting and locating prey concealed by darkness and turbidity. [ABSTRACT FROM AUTHOR]