The two major alkaloids, samandarine and samandarone, were identified in the skin secretion of individual specimens from two populations of the European fire salamander (Salamandra salamandra terrestris) by gas chromatography/mass spectrometry. High intraspecific variability in the ratio of both alkaloids was observed, but also in individual specimens over a period of 4 months suggesting separate metabolic pathways of the compounds. Alkaloid synthesis appears to take place also in liver, testes and ovaries, whereas the larvae of the salamanders are entirely free of alkaloids.