Comparative ultrastructural study of general body epidermis of the hill-stream fishes; Botia almorhae (Teleosti: Botiidae), Homaloptera brucei (Teleostei: Balitoridae) and Schizothorax richardsonii (Teleostei: Cyprinidae)

The aim of the present study is to provide a basis for better knowledge of the surface architecture of the GBE of some hill-stream fishes. The skin of the hill- stream fishes, on the dorsal surface of the body just behind the head, is densely set with scales and composed of an epidermis and a dermis supported by a hypodermis. Noticeable differences exhibited in the patterns of microridges on epithelial cells, distribution of mucous cells and presence of tubercles on the general body epidermis of the hill-stream fishes may be considered as modifications relating to possible difference in the functional requirement at the different locations. The skin has long been recognized to protect the organisms from deleterious environmental impacts (physical, chemical, microbiological). It is also well-known to be crucial for the maintenance of temperature, electrolyte and fluid balance.