Answer for What is the most accepted definition of Small Indigenous Species of Fish?

The most accepted definition of Small Indigenous Species of Fish is as below-
Small indigenous species of Fish (SIS Fish) are those small fishes which attains a maximum length of 25 cm (Felts et al., 1996; Hossain and Afroze, 1991; Hossain et al., 1999).
Bangladesh has approximately 260 indigenous fresh water species where 143 species are classified as small indigenous species (Rahman, 2005).
 
Reference:
Felts, R.A., F. Rajts and M. Akhteruzzaman, 1996. Small indigenous fish species culture in Bangladesh (Technical brief), IFADEP Sub project 2. Development of Inland Fisheries, pp: 41.
Hossain, M.A. and S. Afroze, 1991. Small fish as a resource in rural Bangladesh. Fishbyte, 9: 16-18.
Hossain, M.A., K. Afsana and A.K.M. Azad Shah, 1999. Nutritional value of some small indigenous fish species (sis) of Bangladesh. Bangladesh J. Fish, 3: 77-85.
Rahman, A.K.A., 2005. Freshwater Fishes of Bangladesh. 2nd Edn., Zoological Society of Bangladesh, Dhaka, Bangladesh, ISBN-13: 9789843221803, pp: 86-87.