Species description:
Species name meaning of the marshes, in reference to the usual habitat.

Reproduction:
Sporophytes sporadic in occurrence, maturing in spring to summer, reddish-brown and grooved when mature; gemmif­erous plants frequent through most of the year.

Distinguishing characteristics:
The whitish midrib that is shiny on the back of the leaf is distinctive in dried plants; the leaves are somewhat contorted when dry.

Habit:
Forming extensive dense, yellow-green turfs of erect shoots, of­ten interwoven with red rhizoids.

Similar Species:
Differs from A. androgynum in habitat and size. From A. turgidum, the contorted leaves and the less turgid shoots are useful distinguishing features; A. turgidum also occurs in drier sites. A. acuminatum has pointed leaves but the plants are turgid and leaves do not become contorted when dry.

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:
Aulacomnium palustre var. congestum Boul.
Aulacomnium palustre var. dimorphum Cardot & Thér.
Aulacomnium palustre var. imbricatum Bruch & Schimp.