text: There are two main categories of toxin studied, samandarine and samandarone. There also exist many other compounds, as well as miscellaneous alkaloid secretions. Both samandarine and samandarone are produced by S. atra species. It is hypothesized that salamandarine is more commonly produced in alpine salamanders as a predator defense mechanism, and salamandorones are produced where there is greater infection risk. There is also noted geographic variation in toxin production by alpine salamanders.
  Immunobiology and protection
  Samandarone, a toxin they produce via skin secretion, has noted antimicrobial activity. In one study, this toxin was present where there was infection risk, but at low concentration. There is a wide arsenal of toxins produced by S. atra , many of which are antimicrobial or could be precursors to other protective molecules. Nonetheless, the alpine salamander has been relatively lucky in avoiding infection with amphian chytrid fungus compared to other amphibian species. This dangerous fungal infection, caused by Batrachochytrium dendrobatidis (Bd) has decimated amphibian populations on every continent. Bd is present in the Alps where alpine salamanders live, but in a study performed in 2012, there were no salamanders who tested positive when swabbed. This may be because Bd infections are more common in species who spend more of their time in water, and since the alpine salamanders are terrestrial, they are less susceptible. An alternate hypothesis proposes that S. atra are resistant via their skin microbiome or a produced molecule, thus granting them immunity. This theory is untested, but considering how many salamanders excrete biological toxins, plausible.