Sciuro-hypnum curtum has been synonymized with S. oedipodium, but the present
revision reveals that they are two distinct species although morphological
variation is very broad in both of them. However, molecular delimitation of
these two species (nrITS) is much more sharp. Sciuro-hypnum curtum is a
widespread species in boreal forests of Eurasia, and occurs also in North
America mainly in its eastern part, with solitary localities in the West. Sciuro-hypnum
oedipodium is widespread in western North America, totally absent in the
eastern part of this continent, and is known in Russia in Caucasus and in
Chukotka. Brachythecium holzingeri is synonymized with S. oedipodium.