Structure of Northern River Terrapin
Northern River Terrapin is one of Asia's largest freshwater and brackish turtles. The carapace of Northern River Terrapin is 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; vertebral 2 to 4 sub equal, much broader than long in the young, nearly as long as broad and as broad as the costal in the adult. The postero-lateral border of the third vertebral is strongly concave.
Plastron of Northern River Terrapin
The Plastron of Northern River Terrapin is large and 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 than between the humeral; inguinal large, axillary’s smaller.
Head of Northern River Terrapin
The head of Northern River Terrapin is rather small; snout pointed, produced, directed upwards; jaws with denticulate edge, upper feebly notched mesially. The width of the lower jaw at the symphysis nearly equals the diameter of the orbit. The limbs of Northern River Terrapin are transversely enlarged in band-like scales.
Colour of Northern River Terrapin
Northern River Terrapin has normally the upper surface of shell (carapace) and soft parts are olive-brown, lower surface (plastron) is yellowish.
Breeding of Northern River Terrapin
The male Northern River Terrapin in breeding coloration as having the head and ventral part of the neck black, with the coloration of the dorsal portion of the neck to its base rich crimson or bright red-orange and the whole of the forelimbs as brilliant rosy carmine or rusty to light orange. The hind parts of Northern River Terrapin are dull reddish purple. Their neck and head have a dark brown pigmentation and the base of the neck and forelimbs have a reddish pigmentation. This reddish pigmentation makes the Sunderban River Terrapins a unique species that are widely found in the Sunderbans Mangrove Forest and Sunderbans National Park in West Bengal and Bangladesh.
Concentration of Northern River Terrapin
Northern River Terrapins are found only in West Bengal and Bangladesh, Sundarbans and in captivity in Vawal National Park at Gazipur, Cambodia and Indian states like Odisha and coastal part of Eastern Ghats Mountain Range in India, Indonesia and Malaysia and Regionally extinct in Myanmar, Singapore, Thailand and Vietnam.
Eggs of Northern River Terrapin
Northern River Terrapin is oviparous in nature. It usually lays three clutches of between 10 and 34 eggs each during the breeding season in December-March; when she has laid her clutch of eggs she covers the nest with sand and then rises and falls on the surface to compact the sand.