Pleuroziopsis was segregated
from Climaciaceae into a separate monotypic family Pleuroziopsidaceae by
Ireland (1968). According to Ireland, the most important and unique
characteristic of Pleuroziopsis is a fluting of the stem by streaks of
stem lamellae. However, this pattern of stem fluting is shown to be shared with
the genus Climacium, so Pleuroziopsis is returned to
Climaciaceae.