L. japonica may refer to: * Laminaria japonica, a marine species of brown algae * Leptanilla japonica, an ant species in the genus Leptanilla * , a crane fly species in the genus Limnophila * , a louse fly species in the genus Lipoptena * , a spear-winged fly species in the genus Lonchoptera * Lonicera japonica, the Japanese honeysuckle or suikazura, a flowering plant species native to eastern Asia * Luehdorfia japonica, the Japanese luehdorfia, a butterfly species found in Japan and China