Plagiothecium berggrenianum

Frisvoll

Lindbergia 7: 96, fig. 2a – i. 1982.

Treatment appears in FNA Volume 28. Treatment on page 488. Mentioned on page 484.

Plants in dense tufts, light green to yellowish, glossy. Stems to 8 cm, 1–1.5 mm wide across leafy stem, erect, julaceous. Leaves erect, closely imbricate, ovate or oblong-ovate, symmetric, concave, 1.5–2.5 × 0.8–1.2 mm; margins broadly recurved throughout, entire or denticulate at apex; apex acuminate, not abruptly contracted, usually recurved; costa with one branch sometimes reaching 1/3 leaf length; alar cells rectangular or inflated and oval, 40–60 × 9–24 µm, in 2–4 vertical rows, terminating in 1 cell at base, region triangular or rarely somewhat oval; medial laminal cells 85–141 × 6–12 µm. Specialized asexual reproduction unknown. Sexual condition unknown. Sporophytes unknown.


Habitat: Swales, wet tundra, rocky slopes, cliffs
Elevation: low to moderate elevations (0-1200 m)

Distribution

V28 759-distribution-map.gif

Greenland, N.W.T., Alaska, n Europe (Norway)

Discussion

Plagiothecium berggrenianum is an Arctic species that has been confused with P. cavifolium, or with julaceous forms of P. denticulatum and P. laetum. The acuminate leaves with recurved apices separate P. berggrenianum from P. denticulatum, while the inflated, oval cells in the decurrencies will distinguish it from P. cavifolium and P. laetum.

Selected References

None.

Lower Taxa

None.

"broad" is not a number.

differentiated +
acuminate +
Robert R. Ireland Jr. +
Frisvoll +
decurrent +
lanceolate;ovate +
asymmetric +  and symmetric +
imbricate;distant +
spreading +  and erect +
concave +, oblong-ovate +, oblong-lanceolate +, ovatelanceolate +  and ovate +
cucullate +
dark red +, light-brown +, reddish +, orangebrown +  and yellowish +
arcuate +  and straight +
inclined +, erect +  and cernuous +
oblong;ovoid +
oval +, inflated +  and rectangular +
differentiated +
9um;24um +
Greenland +, N.W.T. +, Alaska +  and n Europe (Norway) +
low to moderate elevations (0-1200 m) +
Swales, wet tundra, rocky slopes, cliffs +
0.02 cm0.2 mm <br />2.0e-4 m <br /> (0.04 cm0.4 mm <br />4.0e-4 m <br />) +
0.15 cm1.5 mm <br />0.0015 m <br /> (0.25 cm2.5 mm <br />0.0025 m <br />) +
concave +, oblong-ovate +  and ovate +
enlarged +
0.08 cm0.8 mm <br />8.0e-4 m <br /> (0.12 cm1.2 mm <br />0.0012 m <br />) +
serrate +, serrulate +  and entire +
denticulate +  and entire +
sexual +  and asexual +
conic;rostrate +
cylindric;fusiform +
oval +  and triangular +
papillose +  and smooth +
orange;redbrown +
curved +  and straight +
elongate +
spheric;ovoid +
imbricate;distant +
6 cm60 mm <br />0.06 m <br /> (8 cm80 mm <br />0.08 m <br />) +
concave +, oblong-ovate +, oblong-lanceolate +, ovatelanceolate +  and ovate +
0 cm0 mm <br />0 m <br /> (8 cm80 mm <br />0.08 m <br />) +
1mm;1.5mm +
Stereodon sect. Plagiothecium +
Plagiothecium berggrenianum +
Plagiothecium +
species +
specialized +
dioicous +, autoicous +  and sexual +
thin +  and thick +
light green;yellowish +