River terrapins of different age cohorts: (from top to bottom) hatchling of about a week old, one year old and two years old.
Carapace moderately depressed, with a vertebral keel in the young, which keel disappears in the adult; nuchal broader than long; first vertebral as broad in front as behind, or a little broader; vertebrals 2 to 4 subequal, much broader than long in the young, nearly as long as broad and as broad as the costals in the adult, the postero-lateral border of the third vertebral strongly concave. Plastron large, strongly angulate laterally in the young, convex in the adult, truncate anteriorly, angularly notched posteriorly; the width of the bridge exceeds the length of the posterior lobe; the longest median suture is that between the abdominals, the shortest that between the gulars, the latter never more than half that between the humerals; inguinal large, axillary smaller. Head rather small; snout pointed, produced, directed upwards; jaws with denticulated edge, upper feebly notched mesially; the width of the lower jaw at the symphysis nearly equals the diameter of the orbit. Limbs with transversely enlarged, band-like scales. Maximum carapace length is 60 cm. Upper surface of shell and soft parts olive-brown, lower surface yellowish. 
In English the Batagur baska has common names of northern river terrapin, batagur, common batagur, four-toed terrapin, river terrapin, giant river turtle, giant river terrapin, mangrove terrapin and Asian river terrapin
Das, Indraneil (1989) "Batagur baska in Orissa" Hamadryad: The Journal of the Madras Crocodile Bank Trust 14(1): 2-3
Gray,J.E. (1857) "Notice of some Indian tortoises (including the description of a new species presented to the British Museum by Professor Oldham)" Annals and Magazine of Natural History 19(2): 342-344