First ever record of a threatened onespot barb fish, Puntius terio (Hamilton) from Arunachal Pradesh, India: A biodiversity hot spot

Arunachal Pradesh is geographically the largest state in North-East region of India with rich lentic and lotic water resources. The state has more than 7000 ha of lentic water and 2000 km of lotic water resources. Arunachal Pradesh is the 18th hot spot of the world in view of the richness of biological diversity. It constitutes high endemism and comparatively higher incidence of rare and threatened taxa. Available literature suggests that Puntius terio has not been reported earlier from the aquatic habitat of Arunachal Pradesh except in West Bengal, Assam, Manipur and Tripura in India, Bangladesh and Pakistan. This fish has incomplete lateral line with 22 to 24 scales on the lateral line, barbels absent, dorsal fin spine smooth and osseous and round golden-edged black blotch on 16th to 18th scales. The present finding of the threatened fish, P. terio requires its conservation in the water system of the biodiversity hot spot, Arunachal Pradesh.   Key words: First ever record, threatened, Puntius terio, Tango Epong stream, Arunachal Pradesh.