The worldwide rare Iwatsukia
jishibae (Steph.) Kitagawa was found to be relatively common in
Khamar-Daban Range near the south end of Lake Baikal (South Siberia). A
detailed description of this species, as
well as differences from allied species are given, and there is a key to genera of Cephaloziaceae
in Russia. Mainly a tropical-subtropical species, I. jishibae has a
disjunct distribution in Central America, West and East Africa, Indian Ocean
islands, Papua-New Guinea, Nepal, Japan, Korea and South Siberia. This species occurs exclusively on rotting
wood. Iwatsukia exigua is
believed to be conspecific with I. jishibae.