Newt
Newts, as with salamanders in general and other amphibians, serve as bioindicators because of their thin, sensitive skin and evidence of their presence (or absence) can serve as an indicator of the health of the environment. Most species are highly sensitive to subtle changes in the pH level of the streams and lakes where they live. Because their skin is permeable to water, they absorb oxygen and other substances they need through their skin. Scientists study the stability of the amphibian population when studying the water quality of a particular body of water.
Laos knobby newt
Laos knobby newt, Tylototriton notialis, is a species of newt in the family Salamandridae. It is only known from its type locality in the Nakai-Nam Theun Biodiversity Conservation Area, Khammouane Province, central Laos. The type locality is an evergreen mixed deciduous–pine forest; the newts were found in and near a small stream. It is likely that Laos knobby newt will also be found in adjacent areas of Vietnam. Based on molecular genetic data, it belongs to the "Tylototriton asperrimus" group of knobby newts. Laos knobby newt is a small newt, with total length of about .