Kerria japonica, a deciduous shrub species native to eastern Asia, in China, Japan and Korea
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Kumba japonica, a rattail fish species found in the waters around Taiwan and southern Japan
Camellia japonica | Lonicera japonica | Cleyera japonica | Fallopia japonica | ''Ulmus davidiana'' var. ''japonica'' | Saccharina japonica | Fatsia japonica | ''Saccharina japonica'' (species synonym ''Laminaria japonica'') | Ranzania japonica | Prunus japonica | Orostachys japonica | Kumba japonica | Kerria japonica | Julia japonica | Inioteuthis japonica | Fauna Japonica | Fagus japonica | ''Ehretia dicksoni'' var. ''japonica'' | Apis cerana japonica |
Fatsia japonica, the fatsi or Japanese aralia, a plant species native to southern Japan
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Fagus japonica, the Japanese blue beech, a deciduous tree species native to Japan
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Fallopia japonica, the Japanese knotweed, a large herbaceous perennial plant species native to Japan, China and Korea
Gleditsia japonica, the Japanese honey locust, a tree species in the genus Gleditsia
Inioteuthis japonica, a bobtail squid species native to the western Pacific Ocean, specifically the waters off China, Taiwan and southern Japan
Julia japonica, a sea snail species found in Wakayama, Honshū, Japan
Kim & S. Lee is a cross of Ulmus macrocarpa with Japanese Elm Ulmus davidiana var. japonica discovered on Seoraksan (Mount Sorak) near the city of Sokcho on the eastern coast of South Korea.