Histological studies of gonads in Neolissochilus hexagonolepis (McClelland, 1839) (Teleostei: Cyprinidae) from Meghalaya, India

Chocolate Mahseer, Neolissochilus hexagonolepis is an important food and game fish of North Eastern region of the country, particularly the high lands of Meghalaya. Reproductive biology of the species has been done under the climatic condition of Meghalaya to understand the gonadal development. The gonadal structure and development stages of germ cells of N. hexagonolepis are described for both sexes. Five stages of development are described based on the histological characteristics of testis and ovary. The kind of development and the presence of postovulatory follicles in ovaries which still contain developing vitellogenic oocytes suggest that N. hexagonolepis spawns over a relatively prolonged period of time.