Sphagnum tenellum
Voy. Îles Afrique. 3: 107. 1804,.
Plants small, slender and weak-stemmed; pale yellow to golden brown, rarely tinged with red; capitulum not especially distinct. Stems pale green to pale brown; superficial cortex of 2–3 layers of enlarged thin-walled cells. Stem leaves ovate-lingulate; 1–1.3 mm, apex broadly rounded; hyaline cells nonseptate, aporose and fibrillose in at least distal half of leaf. Branches 2–3 spreading and 2 pendent leaves not much elongated at distal end. Branch stems green; cortex enlarged, with conspicuously long-necked retort cells. Branch leaves ovate, 1–1.5 mm; straight; not or weakly undulate or recurved when dry; margins entire; hyaline cells short and wide, convex surface with 1–3 small pores per cell and on concave surface with large round wall thinnings in the cell angles; chlorophyllous cells equilateral-triangular in transverse section, broadly exposed on convex surface and just reaching to well-enclosed on concave surface. Sexual condition monoicous. Spores 27–42 µm; both surfaces smooth, proximal surface with distinct bifurcated Y-mark sculpture surrounded by distinct circular border, distal surface with distinct raised border around margins; proximal laesura usually less than 0.4 spore radius.
Phenology: Capsules mature early to mid summer.
Habitat: Wet depressions in a variety of ombrotropic and weakly minerotrophic habitats
Elevation: low to high elevations
Distribution
Greenland, B.C., Man., N.B., Nfld. and Labr. (Nfld.), N.S., Alaska, Maine, N.J., N.Y., N.C., Eurasia.
Discussion
Sporophytes are common in Sphagnum tenellum. The delicate appearance created by the ovate and concave branch leaves as well as the large concave stem leaves make this a usually unmistakeable species.
Selected References
None.