Skeleton of Indian Black Turtle
Species: M. trijuga
The turtle’s Skelton is unique as it’s had a dome shaped shell over the body, an adaptation that protects it from predators. The carapace and plastron each arose from two types of bone, dermal bones that form in the skin and endochondral bone derived from the skeleton. Evolution has intricately linked these two types of bone to produce the shell of modern turtles. The Indian Black Turtle has a shell with the rigid upper part. The carapace consists of 10 trunk vertebrae and their ribs, which are overlain by and fused to dermal plates. Another series of dermal plates forms the perimeter of the carapace. The plastron usually contains four pairs of large plates and a single one centered near the front (the anteromedial plate) these plates are large dermal bones, although the anterior ones may contain parts of the shoulder girdle. The shell is variously modified and shaped to meet the needs of defense, feeding, and movement.
About the animal
The Indian black turtle is a medium-sized freshwater turtle from South Asia. Despite its common name, the colour of this attractive turtle varies hugely, ranging from reddish to dark brown or black, often with three yellowish ridges running along its length. The underside, or ‘plastron’, is typically a uniform brown with a light trim around the edge. The head of the Indian black turtle may have a scattering of orange or yellow spots, with the intensity of the colour of this spotting varying between the six different subspecies. The limbs and tail are generally a grey colour. This turtle has a medium-sized, broad head with a rather short snout, and the feet are fully webbed, aiding with swimming in its aquatic environment.