Species description:
Species name meaning somewhat like imponens, referring to its resemblance to H. imponens The name imponens means imposter, indi­cating that this species strongly resembles, at times, other species of Hypnum.

Reproduction:
Sporophytes frequent, erect to suberect, especially when unripe (green), reddish-brown when ripe.

Distinguishing characteristics:
The yellow-green colour, abundant regular pinnate branching, coupled with the usually non-terrestrial habitat and the erect to suberect sporangia are valuable features.

Habit:
Forming reclining, glossy, pale yellow-green mats of regularly pinnate plants loosely attached to the substratum.

Similar Species:
See notes under H. circinale. Ptilium crista-castrensis is of a similar colour but the plants are very regularly pinnate, tend to be erect to suberect, rather than reclining, and are generally terrestrial within forests. The leaves of Ptilium are pleated, a feature absent in the Hypnum, and shoots of the Hypnum frequently grow with the apex pointing downward rather than consistently upward as in Ptilium. Spo­rangia of Ptilium are strongly inclined.

If more than one illustration is available for a species (e.g., separate illustrations were provided for two subspecies) then links to the separate images will be provided below. Note that individual subspecies or varietal illustrations are not always available.

Illustration Source:  Some Common Mosses of BC

Synonyms and Alternate Names:
Hypnum subimponens var. cristulum Kindb.