User:Salamandra2021/sandbox

Conservation Status

Takahashi et al found that a large male salamander called "den master" stays in the nest with larvae until the following spring. The Japanese giant salamander can grow to a length of 5 feet (1.5 m) and a weight of 55 pounds (25 kg). The largest wild specimen on record weighed 58 lb (26.3 kg) and was 4.46 ft (136 cm) long. It is the third-largest amphibian in the world, only smaller than its close relatives, the South China giant salamander and the Chinese giant salamander. The brown and black mottled skin of A. japonicus provides camouflage against the bottoms of streams and rivers. It has very small eyes with no eyelids and poor eye sight. Its mouth extends across the width of its head, and can open to the width of its body.

A. japonicus possesses large skin folds on its neck that effectively increase its overall body surface area. This assists in epidermal gas exchanges, which in turn regulates carbon dioxide and oxygen exchange with the water. Capillaries in the surface of the skin facilitate this gas exchange.

The Japanese giant salamander can be distinguished from the Chinese giant salamander by the arrangement of tubercles on the head and throat. The tubercles are larger and more numerous compared to the mostly single and irregularly scattered tubercles of the Chinese giant salamander. The snout is also more rounded, and the tail is slightly shorter.