A new natural product, named selagoline, and two known alkaloids, huperzine A and serratidine, were isolated from Huperzia selago ( Lycopodiaceae) collected in Iceland. Their structures were determined using 600 and 800 MHz one- and two-dimensional NMR methods supported by Fourier-transform mass spectrometry. Possible role of selagoline as a precursor of 5,15-oxidolycopodane, a component of the classical alkaloids L28 and L31, is discussed.