Water Sphagnum

The sporophytes of Sphagnum inundatum are uncommon. The ovate, concave branch leaves that are occasionally subsecund give this species an appearance similar to that of S. subsecundum, from which it can usually be distinguished by its larger size. Sphagnum lescurii typically has distinctly larger stem leaves and capitulum branches that can be quite turgid and curved in open-grown forms.

The names Sphagnum bavaricum Warnstorf and S. bushii Warnstorf & Cardot have been applied to this taxon.

Plants moderate-sized, green in the shade to variegated yellow or orange or both in open habitats; capitulum typically rounded. Stems green to brownish or yellow; superficial cortex of 1 layer of enlarged, thin-walled cells. Stem leaves lingulate to triangular-lingulate, 0.9-1.2 mm, apex rounded, usually ¹/3-¹/2 of leaf fibrillose; hyaline cells usually fibrillose in distal ¹/3-¹/2 of leaf, on convex surface near apex with 1-3 pores per cell, on concave surface near apex 1-4 pores per cell. Branches arched but rarely curved and contorted. Branch fascicles with 2-3 spreading and 2-3 pendent branches. Branch leaves ovate, 1-1.5 mm, straight to slightly subsecund; hyaline cells of convex surface with numerous ringed pores along the commissures (12-22 per cell), 0-3 pores per cell on the concave surface. Capsule with few pseudostomata. Spores 30-37 µm; finely papillose on both surfaces, indistinct raised Y-shaped sculpture on distal surface; proximal laesura 0.5 spore radius or less.

Plants rather robust, grayish green or pale brown, in compact cushions. Stem cortex in 1 layer, hyaline cells without fibrils; central cylinder rather thick, yellowish brown. Stem leaves 0.4–0.7 mm × 0.3–0.6 mm, ligulate, rounded obtuse and lacerate at the apex; borders narrow above, clearly widened below; hyaline cells undivided (sometimes divided), often without fibrils and pores, rarely with the traces of fibrils in the upper cells and with scattered pores on the ventral surface. Branches in fascicles of 3–5, with 2–3 spreading. Branch leaves 1.0–1.4 mm × 0.5–0.6 mm, broadly ovate-lanceolate, strongly concave, somewhat secund, gradually narrowed and margins involute at the apex, borders narrowly differentiated; hyaline cells densely fibrillose, with numerous, ringed pores in commissural rows on the dorsal surface, with fewer pores on the ventral surface; green cells in cross section narrowly elliptic or nearly rectangular, centrally located, exposed on both surfaces. Dioicous. Sporophytes not seen.

Distribution: China, Japan, Europe, and North America.

Habitat: in bogs and on humic soil of grasslands or under forests, sometimes submerged in water.

Sphagnum auriculatum var. inundatum (Russow) M. O. Hill; S. novo-foundlandicum Warnstorf; S. subsecundum var. inundatum (Russow) C. E. O. Jensen

Sphagnum inundatum var. perfibrosum P. de la Varde, Rev. Bryol. Lichénol. 10: 136. 1938.

Sphagnum inundatum is a species of moss belonging to the family Sphagnaceae.

It has cosmopolitan distribution.