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.
Red-tailed knobby newt
The red-tailed knobby newt is a highly toxic newt. They can kill a human that has a weak body or a baby.
The Kweichow Crocodile Newt (T.kweichowensis) is part of the Genus known Tylototriton which consists of 11 known subspecies and possibly even more yet to be named. All Tylototriton are considered highly toxic due to their defense mechanism which is being able to use the tips of its ribs to pierce the insides of the Orange Warts along its sides which secrete the toxin. However they are a fairly docile species so this rarely can happen.