Sphagnum sect. Isocladus

Plants coarse and robust; usually found floating, submerged or stranded; capitulum not apparent, leaves crowded into a tuft; deep green throughout or dark reddish brown to blackish brown with yellowish branch tips when wet and shiny pale green to straw colored or brown when dry. Stems green to brownish, superficial cortex of 2–3 layers of inflated, thin-walled, efibrillose, non-ornamented, aporose cells. Stem leaves much smaller than branch leaves, broadly triangular with a rounded apex, border entire, hyaline cells rhomboid, efibrillose and non-ornamented; convex surface aporose; concave surface with 0–5 round or oblong pores with either 1 central pore or pores in a single row. Branches more or less monomorphic. Branch fascicles with 2–3 branches. Branch stems green, surrounded by 1–3 layers of enlarged, thin-walled, efibrillose, non-ornamented, mostly aporose cells. Branch leaves lanceolate, linear-lanceolate to ovate-lingulate, apex tubular and involute or flat and rounded, with numerous small pores (8–60 per cell) on the convex surface in 1–3 irregular rows, nearly aporose on the concave surface; chlorophyllous cells rectangular in transverse section and equally exposed on both surfaces. Sexual condition dioicous. Capsule with few pseudostomata or pseudostomata absent. Spores 25–35 µm; smooth to finely papillose on proximal and distal surfaces, conspicuous bifurcated Y-mark sculpture on distal surface; proximal laesura less than 0.5 spore radius.

Distribution

North America.

Discussion

Species 2 (2 in the flora).

Selected References

None.

Lower Taxa

Sphagnum cribrosum, Sphagnum macrophyllum

Key

1	Branch leaves with 20-40 pores, each less than 0.25 width of cell, mostly in 2 rows, branch leaves ovate-ligulate with a broad, rounded, truncate apex.	Sphagnum cribrosum
1	Branch leaves with 8-12 pores, each more than 0.25 width of cell, mostly in 1 row, branch leaves lanceolate to linear-lanceolate with a narrow tubular apex.	Sphagnum macrophyllum