Toxin-producing bacteria can make this newt deadly
Microbes growing on skin produce tetrodotoxin, a paralytic chemical also found in pufferfish
Rough-skinned newts (Taricha granulosa) can harbor bacteria on their skin that produce the paralytic neurotoxin tetrodotoxin. Newts use the poison as a defense against predatory snakes.
Gary Nafis, CaliforniaHerps.com