Dichotomous key to European species of Sphagnum Part 2

Branch leaves short and strongly concave throughout. Branches blunt. Stem cortex 2-layered (1- or 3-layered in parts): outer cells occasionally with a large pore or thinning. Plants dull green or olive, sometimes purplish but never red. Local to rare in mesotrophic locations which are, at least periodically, flooded.

Sphagnum platyphyllum

Upper branch leaves longer and narrower than the lower. Branches blunt or, commonly, somewhat, acute and tapering. Stem cortex 1-Iayered, rarely with occasional.pores. Plants sometimes distinctly red. Common and widespread in oligotrophic to mesotrophic pools and ditches or hollows; also on dripping rocks.

Sphagnum auriculatum

Stem,cortex of 2 or more layers. Internal cylinder, of stems always pale, pale brown, never dark brown or blackish. Plants small-leaved.

Rare to locally frequent in eutrophic mires.

Sphagnum contortum

Stem cortex always single-layered. Internal cylinder of stem commonly dark brown or blackish, at least in part. Plants small or, large-leaved. Frequent to common in oligotrophic to mesotrophic mires or  pools, on wet rocks or along seepage lines.

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Stem leaves small (less than 1.2 mm long): fibrillose only near the apex (fibrils often incomplete, rarely absent). Branch leaves small, the lower usually curved, asymmetric and secund. Fascicles of fully developed plants with 5-6 .branches (if small-leaved but with .3-4 branches per fascicle and stem leaves fibrillose for more than one third of length, see S. auriculatum)

Sphagnum subsecundum subsp. subsecundum

Stem leaves at least 1.2 mm long: fibrillose at least in upper quarter and commonly to about two-thirds from apex. Branch leaves rarely under 1.3 mm long, the lower curved or straight. Fascicles of fully developed plants commonly with only 3 or 4 branches.

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Fascicles of 3-4, rarely 5, branches. Branch leaves mostly symmetrical, ± suberect and convolute. Branches ± tumid, often curved and horn-like. Stem leaves lingulate to spatulate: fibrillose at least in upper third and often to below half-way. Hyaline cells of stem leaves with fewer pores on the adaxial surface than on the abaxial: abaxial pores often in regular rows along the commissures. Plants often very robust, sometimes tinged wine-red. Common in oligotrophic or mesotrophic hollows and pools, springs and seepage lines and on wet rocks.

Sphagnum auriculatum

At least some fascicles with 5 well-developed branches (except in weak plants). Branch leaves often curved and asymmetric near the branch bases, mostly erect-spreading. Branches rarely tumid, never curved and horn-like. Stem leaves triangular-lingulate, narrowed above the insertion: fibrillose one quarter to one third from apex, rarely to mid-leaf. Hyaline cells of stem leaves with more numerous pores on adaxial surface than on abaxial, or both surfaces multiporose. Plant often orange but never red. An uncommon species of mesotrophic mires and stream-sides.

Sphagnum subsecundum subsp. inundatum

Stem leaves shortly lingulate, as wide or wider above than at insertion; fimbriate with a wide zone of apical resorption: hyaline cells enlarged and lacking fibrils. Stems dark brown to almost black. Plants-brown.

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Stem leaves as wide as, or narrower above than, at insertion: subacute to obtuse; if narrowly fimbriate, then stems and plants pale. If plants brown, then stem leaves either ± acute or with fibrils. Stems mostly pale, sometimes dark.

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Plants robust. Stem leaves large (ca 1.0 mm wide): expanded above and fimbriate across the whole upper part. A widespread plant of the boreal to arctic area of N and NE Europe.

Sphagnum lindbergii

Plants small. Stem leaves small (less than 0.8 mm.wide): not, or only slightly wider at apex than insertion and fimbriate only across the narrowed apex. A rare arctic to sub-arctic species of the extreme NE of Europe.

Sphagnum lenense

Branch leaves (except for a few basal ones) narrowly lanceolate to linear-lanceolate, more than 3 times (often more than 5 times) as long as wide. Hyaline cells on convex surface of branch leaves without pores, or with a single pore in the apical angle. Stem leaves ± acute; fibrillose above. Plants yellowish green to pale green: common in pools and wet hollows.

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Branch leaves (especially those of pendent branches) mostly less than 3 times as long as wide or, if longer, then hyaline cells with abundant pores or stem leaves without fibrils. Stern leaves various, mostly with acute apices. Plants various, sometimes brown.

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Photosynthetic cells of branch leaves in TS, trapezoid, widely exposed on both leaf surfaces. Branch leaves commonly more than 4 times as long as wide. Fascicles with poorly differentiated or undifferentiated pendent branches. Plants often pale green: widespread, usually in bog

pools or wet hollows.

Sphagnum cuspidatum

Photosynthetic cells of branch leaves in TS, triangular, not, or barely, reaching the concave leaf surface. Branch leaves rarely more than 3 times as long as wide. Fascicles with slightly to moderately differentiated pendent branches bearing ovate-lanceolate to lanceolate leaves.

Plants usually deep green.

Sphagnum recurvum var. mucronatum

Plants green, yellowish or tinged brown: if overall brown, then stem leaves acutely pointed or apparently mucronate, strongly deflexed; non-fibrillose.

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Plants brown, except in shade: if paler, then stem leaves spreading, .obtuse and concave; mostly fibrillose, at least near apex.

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Stem leaves triangular to oval-triangular: apices acute or mucronate due to incurved or 'pinched' margins: if narrowly obtuse, then branch leaves strongly 5-ranked, more than 1.4 mm long and stem cortex ± distinct around whole of circumference.

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Stem leaves shortly lingulate to triangular-lingulate: apices broadly rounded-obtuse, sometimes notched, torn or fimbriate: if apparently mucronate, then branch leaves mainly less than 1.4 mm long and stem cortex distinct only adjacent to leaf and fascicle insertions.

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Branch leaves widest one quarter to one third above, insertion. Stems pale, green or yellowish. Branches long (usually more, than 15 mm). Plants green to yellow-orange, occasionally olive-brown. Common and widespread, often forming extensive carpets in mesotrophic mires.

Sphagnum recurvum var. mucronatum

Branch leaves widest at, or just below, half-way. Stems brownish, rarely pale. Branches Short (usually less than 15 mm). Plants gold, golden brown or rich brown. Local in lowlands, mainly towards south and west.

Sphagnum pulchrum

Stem leaves deeply notched or bifid, appearing as if partially torn down the middle. Branch leaf apices narrow, slightly spreading when dry, ± acute and composed of undifferentiated prosenchymatous cells (except in weak plants). Plants robust: shade-tolerant in wet oligotrophic to mesotrophic mires. A sub-arctic and boreal species, common in the north but more local or rare in the south.

Sphagnum riparium

Stem leaves not deeply notched or bifid, sometimes minutely notched. Branch leaf apices narrowly truncated and composed of both hyaline and photosynthetic cells.

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