Physcomitrium immersum
in A. Gray, Manual, 648. 1848,.
Plants light green. Stems 2–3 (–4) mm. Leaves obovate to ovatelanceolate, distal leaves 2–3 mm; margins toothed or occasionally smooth distally; costa subpercurrent to short-excurrent. Specialized asexual reproduction absent. Seta 0.5–1.2 mm. Capsule immersed, 1–1.2 mm, broadly cupulate; neck short, indistinct; exothecial cells irregular hexagonal or oblong, walls somewhat unevenly thickened; suboral cells consisting of 1–3 rows of short-rectangular cells. Spores 30–38 µm, papillose.
Phenology: Capsules mature late fall–spring.
Habitat: Wet soil in disturbed places
Elevation: moderate to high elevations
Distribution
B.C., N.B., N.S., Ont., Que., Colo., Iowa, Ky., La., Md., Minn., N.J., Oreg., Pa., Tex., Wash., Wis., South America
Discussion
Physcomitrium immersum is easily recognizable by its immersed, broadly cupulate capsules that are usually clearly visible within the spreading leaves.
Selected References
None.