They're amphibians, live in arid or moist habitats - some species are arboreal, others are solely aquatic but most maintain a life cycle that has them aquatic for the first few stages of their life and then becoming largely terrestrial during adult hood until it is time to mate. All Salamanders are poisonous, they naturally excrete a mucus that acts a natural lubricant, maintaining epidermal hydration and also making them slippery - which works as a good defence against predators. Ingestion or introduction of their poison into bloodstream can cause varying effects as they possess a variety of different poison - perhaps the most notable of which is tetrodotoxin - the most powerful non-protein toxin known to man. Some Salamanders are even venomous, as they posses the ability to expand their rip cage - resulting in poison coated ribs protruding out through their flesh and stabbing into would be predators. Others are capable of spraying poison out of their glands, which can dissuade predators and prove to be a problem should it encounter a sensitive area such as the eye membranes.
Salamanders also possess an astounding regenerative ability, they're capable of regenerating from wound and can even regenerate whole limbs with ease. As a result some of their defensive mechanism involve self mutilation , such as their ability to detach their tail from their body and have it wiggle on the ground to distract predators, or protruding their ribs spines out from their body, since they do not really have to worry about wounds.
From their manga we've seen that Salamanders are capable of spewing poison, can burrow beneath ground, grow to abnormal sizes and are fairly durable.