E-Flora BC: Electronic Atlas of the Flora of British Columbia

Species description:
Genus name referring to the irregular holes in the peristome teeth. Species name noting the large, hood-shaped calyptra.

Reproduction:
Sporophytes frequent in spring; the sporangia are smooth when ripe.

Distinguishing characteristics:
The rounded tufts with conspicuous hair points on the leaves, the semi-arid climate restriction, and the bell­shaped calyptrae will separate this species.

Habit:
Forming whitish to grayish, rounded tufts; the hair points on the leaves are conspicuous and create the grayish appearance of the tufts.

Similar Species:
Several species of Grimmia resemble this moss, but in Grimmia the calyptrae are never bell-shaped and only partially enclose the sporangium. Technical microscopic features also distinguish Cos­cinodon from Grimmia. Unfortunately species of Grimmia of similar form are frequent in the semi-arid interior. G. pulvinata, which super­ficially resembles C. calytratus, has a curved seta unlike the straight seta in Coscinodon; the sporangia are grooved when ripe in Grimmia pul­vinata, smooth in Coscinodon.