The moss species Pseudocrossidium obtusulum (Lindb.) Crum & Anderson is reported for the state of Montana. Recent systematics of the genus Pseudocrossidium in North America is discussed.
Eckel, P. M.; Hoy, J. A.; and Elliott, J. C.
"Pseudocrossidium obtusulum (Pottiaceae, Bryopsida) new to Montana with a key to North American species in the genus,"
Great Basin Naturalist: Vol. 57
, Article 9.
Available at: https://scholarsarchive.byu.edu/gbn/vol57/iss3/9