SURFACE ARCHITECTURE OF THE SKIN OF THE INDIAN CATFISH, BAGARIUS-BAGARIUS (HAMILTON) (SISORIDAE, SILURIFORMES)

The skin surface of Bagarius bagarius was observed primarily by SEM. The epidermis was differentiated into polyhedral, epidermal plaques, separated by deep epidermal furrows. These structures showed significant modifications, associated with their physiological status, in their surface architecture, the epidermal plaques being keratinized and the furrows non-keratinized and mucogenic. The epithelial cells of the keratinized plaques supported projections of fine bristles (unculi). Mucous cells and taste buds were absent. In the non-keratinized mucogenic furrows, the epithelial cells were characterized by intricate patterns of microridges, mucous cells being irregularly distributed and taste buds generally located on epidermal protuberances. The boundaries separating adjacent, keratinized epithelial cells appeared more distinct than those of the non-keratinized mucogenic epithelial cells. The structural peculiarities in the surface sculpture of the skin of B. bagarius apparently reflect functional adaptations.