1b. Bryoxiphium norvegicum ssp. japonicum (Berggr.) Löve & Löve 虾藓东亚变种 xia xian dong-ya bian-zhong
Bryologist 56: 197. 1953. Eustichia japonica Berrgr. in Geh., Flora 64: 290. 1881. Bryoxiphium japonicum (Berggr.) Löve & Löve, Bryologist 56: 78. 1953. Type. Japan, F. R. Kjellman s.n. 1879.
Bryoxiphium savatieri (Husnot) Mitt., Trans. Linn. Soc. London, Bot., sér. 2, 3: 154. 1891. Eustichia savatieri Husnot, Rev. Bryol. 10: 85. 1883. Type. Japan. Savatier s.n.
This subspecies differs from the typical Bryoxiphium norvegicum ssp. norvegicum in that its perichaetial leaves are sharply serrate, especially at the tips, and the dorsal lamella of vegetative leaves are in 2–3 rows of cells often extending from the tip to the base, while in B. norvegicum ssp. norvegicum its perichaetial leaves are only sinuose at the tips, and the dorsal lamella of vegetative leaves are in 1 or 2 rows of cells, usually not reaching the leaf base. The stem leaves of B. norvegicum ssp. japonicum are abruptly obtuse-cordate at the tips with an obviously excurrent, serrulate costa, while those of B. norvegicum ssp. norvegicum are acute at the tips with a percurrent to shortly excurrent, subentire costa. Furthermore, plants of B. norvegicum ssp. japonicum are generally larger, 3–5 cm high, while those of B. norvegicum ssp. norvegicum are smaller, usually 1–3 cm high.