Three new lycopodine-type alkaloids, 4α-hydroxyanhydrolycodoline (1), 4α,6α-dihydroxyanhydrolycodoline (2), and 6-epi-8β-acetoxylycoclavine (3), and an artifact, lycoposerramine G nitrate (4), along with seventeen related known compounds, were isolated from the club moss Lycopodiumjaponicum Thunb. ex Murray (Lycopodiaceae). Their structures were elucidated by extensive spectroscopic methods as well as X-ray analysis. Compounds 1–4 were evaluated for their acetylcholine esterase inhibitory activity.Electronic supplementary materialThe online version of this article (doi:10.1007/s13659-014-0027-1) contains supplementary material, which is available to authorized users.