Unlike some other moss species, C. imponens lacks a hyalodermis but possesses a weak central strand.

The leaf margins are either flat or weakly recurved at the base, exhibiting serrulations towards the distal end or rarely being nearly entire.

C. imponens is dioicous, meaining male and female reproductive structures are produced on separate plants.

C. imponens is characterized by its pigmented and heterogeneous alar cells, reddish stems, long-toothed foliose pseudoparaphyllia, and nearly erect cylindric capsules.

Its distribution spans across Greenland and several Canadian provinces such as New Brunswick, Newfoundland and Labrador, Nova Scotia, Ontario, and Prince Edward Island.