Examination of the alkaloids obtained by methanol extraction of Lycopodium clavatum var. inflexum collected in the Eastern Transvaal resulted in the isolation of five alkaloids: four known C16 compounds (lycopodine, dihydrolycopodine, lycodoline, fawcettimine) and a new C17 compound named lycoflexine, which possesses a carbon-nitrogen skeleton differing from previously reported alkaloids in this group. Lycoflexine (C17H25NO2) was characterized via spectral data (IR showing carbonyl absorption at 1740 and 1695 cm⁻¹, active methylene at 1410 cm⁻¹; NMR revealing a secondary C-methyl group and no olefinic protons; MS with parent peak at m/e 275 and base peak at m/e 84) and X-ray crystallography (lycoflexine hydrobromide, monoclinic space group P2₁, R-factor 9.7%), confirming a tetracyclic structure. Its absolute stereochemistry was established using a chiroptical method (CD spectra). Lycoflexine differs from fawcettimine by a methylene bridge linking nitrogen and C-4, and can be synthesized from fawcettimine via an intramolecular Mannich reaction with formaldehyde (ca. 50% yield). Experiments (extraction with 5% aq. HCl, negligible formaldehyde in extracts, detection in plant ether extract) confirmed lycoflexine is a natural alkaloid present in the plant.