Sphagnum steerei

R. E. Andrus

Bryologist 90: 218. 1987,.

Basionym: Sphagnum imbricatum var. arcticum Flatberg Kongel. Norske Vidensk. Selsk. Skr. (Trondheim) 3: 46. 1984
Treatment appears in FNA Volume 27. Treatment on page 54. Mentioned on page 48, 52.

Plants moderate-sized to large, compact and stiff-stemmed with upswept branches; dark green and brown, dark chesnut brown, brown to blackish brown, often with bluish tinge when dry; forming dense low to moderately tall hummocks. Stems dark-brown, superficial cortical layer with spiral reinforcing fibrils visible, usually 2 or more pores per cell, comb-fibrils lacking on interior wall. Stem-leaves to 1.2 × 0.8 mm; rarely hemiisophyllous; hyaline cells mostly nonseptate, comb-lamellae usually absent, but sometimes weak. Branches short and blunt-tipped, leaves spreading. Branch fascicles with 2 spreading and 1 pendent branch. Branch stems with hyaline cells nonornamented, no or weak funnel-like projections on the end walls of cortical cells, cortical cell-walls usually with large round pores. Branch leaves ovate to ovate-elliptical, 1.6–2.2 × 1 mm; hyaline cells on proximal half of convex surface with round to elliptic pores along the commissures; comb-lamellae on hyaline cell wall where overlying chlorophyllous cells; chlorophyllous cells broadly triangular in transverse-section and well-enclosed on convex surface, end wall not thickened. Sexual condition dioicous. Capsule unknown. Spores unknown.


Habitat: Commonly in firm-bottomed poor to medium fen vegetation, subarctic to arctic regions
Elevation: low to moderate elevations

Distribution

V27 19-distribution-map.gif

Man., N.W.T., Nunavut, Que., Yukon, Alaska, e Asia

Discussion

Sphagnum steerei is usually easily recognized in the field by its dense growth habit and dark brown color. Its ecology is somewhat unclear due to taxonomic confusion with S. imbricatum in the strict sense and S. austinii (R. E. Andrus 1987). The latter is the only species in the imbricatum complex that occurs where S. steerei does. Contrary to the view of H. A. Crum (1997), S. steerei is quite distinct from S. affine and S. austinii. There is no range overlap with either of those species and the macroscopic appearance is also quite different.

Selected References

None.

Lower Taxa

None.
... more about "Sphagnum steerei"
cucullate;rounded +
Cyrus B. McQueen† +  and Richard E. Andrus +
R. E. Andrus +
Sphagnum imbricatum var. arcticum +
differentiated +
ratio +, length +  and width +
0.16 cm1.6 mm <br />0.0016 m <br /> (0.22 cm2.2 mm <br />0.0022 m <br />) +
ovate +  and ovate-elliptical +
pendent +, spreading +  and upswept +
1 +  and 2 +
slender +
differentiated +
chlorophyllous +
strengthened +
well-enclosed +
nonornamented +
ornamented +
triangular +
enlarged +
fibrillose +
spherical +
2 cm20 mm <br />0.02 m <br /> (?) +
monoicous +, dioicous +  and sexual +
Man. +, N.W.T. +, Nunavut +, Que. +, Yukon +, Alaska +  and e Asia +
low to moderate elevations +
dioicous +  and sexual +
unthickened +  and thickened +
isophyllous +, hemiisophyllous +  and anisophyllous +
Commonly in firm-bottomed poor to medium fen vegetation, subarctic to arctic regions +
inconspicuous +  and conspicuous +
Round (?) +  and Elliptic (?) +
funnel-like +
ornamented +
tetrahedral +
hemiisophyllous +
lingulate;ovate-lingulate +
0mm +  and 0.8mm +
dark-brown +
differentiated +
round +  and elliptic +
Sphagnum steerei +
Sphagnum sect. Sphagnum +
species +
swollen +
bluish tinge +, brown +  and blackish brown +
moderate-sized +  and large +